How To Hack Yourself: Public Speaking Series

Public squeaking: A complete guide

6 mistakes beginners make… and how to avoid them

Cassie Kozyrkov
15 min readJun 9, 2018

Offstage, I am a data scientist, leader, and decision intelligence engineer. When I’m invited to give a talk, I turn into a theatre company of one. Everything from actor to director to costume designer.

The bad news is that the same goes for your talk, whether you know it or not. Unfortunately the skills that got you the speaking position might be entirely different from what you need to dazzle your audience.

The good news is that industry and academia are stuffed to the gills with novice speakers who don’t realize that public speaking is theatre, so it’s fairly easy to set yourself apart in a crowd of newcomers to the stage. To help you out, here are some practical tips along with a list of newbie mistakes to avoid.

Planning your content

Speech length

A professional speaker finishes on time. That means planning on a shorter speech that the maximum talk length. Since I know I like to improvise a little to keep my speech from feeling stiff, I will plan creating content that fills 75% of the available time.

Always have topics in reserve that you could throw in just before your closing remarks if you run short, though ending early is usually okay. Unless you’re the opening act, conference organizers will thank you for balancing out all the ramblers who went over their allotted time before you.


The fewer words the better. Your slides only really serve three good purposes: entertainment, illustration, and roadmap. Anything else is distracting your audience from listening to you. Your slides should highlight what you’re talking about.

In early iterations of a talk (in private or with my friends), I’ll use dense slides (to remind myself) and drop most of the text as soon as I’m comfortable with the script.

If your talk will be recorded, you should be prepared for your slides not to make it to your video. As I learned the cringingly hard way, if you have a sound bite that sounds silly without your slides, it’s best to change it.

Equations and jargon

Although I come from a field that loves equations (statistics), you’ll find almost none in my talks. (Here’s why.) To know whether you’ve used too many, try my Chinese character exercise.

Public speaking vs teaching

There’s a myth that public speaking equals teaching. Wrong job. Public speaking is entertainment. So where do the teaching skills come in? Designing the speech so that your audience learns something.

The teaching skills come into play before you hit the stage and help you craft your message. The teacher in you is the playwright, but the actor in you wins your audience’s hearts.

Be authentic

When I say you’re an actor playing a role, that doesn’t mean you’re inauthentic. Your role should be you. Or, more precisely, your personal brand. You might be angry at the traffic fiasco on the way to the talk, but the audience doesn’t need to know that unless your personal brand involves being grumpy all the time.

The biggest mistake is not meditating on your personal brand before you ever step onto a stage.

Mastering the stage

Stage type

Standard: Don’t turn your back on the audience, but feel free to roam around as much as you like. (But do respect any no-fly zones the camera crew marks out.)

Podium/restricted: Restricted space with nowhere else to stand is the only circumstance under which I’ll stand behind a podium.

Exhibit A: Using a podium as nature intended. Video link.

Obstacle course: Sometimes you’ll get a stage that’s set up for other purposes, such as a panel (so it’s full of chairs). Before you start talking, scan the space for a trip-free zone, then stick to it. As a clumso who has tripped on stage (and even fallen off the back of one), the only thing to do if an obstacle gets you is to make a quip and move on. Channel the I-meant-to-do-that look cats get after a fall.

Coliseum: Challenge mode! You’ll feel bad about turning your back on your audience, which might push you into whirling dervish mode. Stop. Breathe. The trick is to turn 90 degrees every 3–5 minutes. No twirling! (I’ve made this mistake as a rookie.)

Catwalk: Like the circular stage, you’ll have to have your back to someone. Don’t try to avoid it by staying off the catwalk. I recommend heading to the center of the catwalk and staying there, turning 180 degrees every 3–5 minutes.


I never use a script that involves full sentences because the audience can usually tell when I’m reading. It takes a lot of special training to make reading sound like pure speaking on stage. Instead, I stick to a handful of keywords to indicate topics and slide transitions for a new speech.

Panels and other formats

This article is about solo talks. Here are my advanced guides to other formats:

Practice makes perfect

No professional speaker would skip rehearsing. In fact, my mentor has a name for speaking after two dry runs: “winging it.”

If you’re tempted to wing it anyway — you adrenaline junkie you — you should still respect your audience enough to meet this absolute minimum: it’s your duty to know your topic transitions cold, without notes, and you should always know what’s on the next slide if you’re using slides.

Intentionally rehearsing gestures is a good idea — simply set your phone camera to video mode during a dry run, then watch. Sometimes I record my script and mime gestures (gestures always were a particular weak spot of mine). Hate watching yourself or listening to your own voice? I did too, and then I forced myself to get better. Besides, if the mics are set loud enough, you’ll hear that voice you’re uncomfortable with during the talk. Get comfy in advance!

In addition to practicing your lines, ask to visit the space and play with the equipment so there are no surprises. Try to get your slides clicked through before you present.

Audience size

For me, each of these room sizes was special when I experienced it for the first time:

20 — Most of us experience this as kids and the first time it happens, we’re terrified. I stared at my shoes and mumble-read my little speech about cinnamon from a script I clutched in shaky hands. In many ways, 20 is the most challenging audience size because of the expected personalization and the higher chance someone interrupts you, derailing your train of thought.

50 — Getting used to this one feels like the milestone between thinking of yourself as wobbly versus confident.

100 — This tends to be a scary milestone for grownups. For me, it was the most intimidating one. I couldn’t sleep the night before. It might help you to find two smiley faces in the crowd: one in the first three rows center, one in the back of the room. Ignore the others and move your gaze between these two. It’ll look fine to everyone else and you might feel more relaxed.

200 — The first time I used a mic out of necessity rather than choice. You’ll notice the equipment requirements changing rapidly between 100 and 200.

500 — The first room that felt “significant” to me after a staple diet of 100–300 person gigs. This is where you rapidly start losing audience feedback, especially if the room is dimly lit.

1000 — Just kidding. The lights are a bit different, but it doesn’t feel like anything new if you’re used to 500.

10000 — Anything bigger than 3000 means the lighting probably makes it very difficult to see your audience’s faces. They’re not even looking at you, they’re looking at the big screens with your face on them. You’d think a number like 10,000 is scarier than 100, but actually you feel almost alone in the room because it’s hard to see individual faces and connect with them. The trick here is to do your best even if you’re missing the audience feedback you’re used to.

Take lessons

There is such a thing as speech coaching, and chances are that if you’re admiring a talented speaker, they’ve had lessons. Voice, pronunciation, pace, gestures, body language, and delivery can all be improved with practice. There are many neat tricks they’ll teach you, for example you can rehearse with a pencil across your mouth to train your tongue into better annunciation. If you’re getting serious about a public-speaking career, invest in a professional speech coach.

Warm up

Speech coaches will tell you to run through a series of power poses (e.g. arms out like a star!), tongue twisters (e.g. “You know you need unique New York.”) and facial muscle warmups (e.g. squeak like a mouse then roar like a lion, repeat) designed to simulate smiling/laughing. This is good advice, so listen to them, don’t listen to me, since I do this once every… never. (Don’t tell my coaches!)

I do warm up, though, but I do it by talking to a few people guaranteed to make me feel cheerful. They’re my secret weapon. (Thanks, guys!) Sometimes they’re out of my timezone, though, so I sing along to a cheerful playlist and watch something on YouTube that puts me in the right zone. (If you don’t have a showtime playlist, make one now. You need a bag of cheap tricks to get your brain back into speaking gear if there’s a curveball, and your personal playlist is one of the most effective.)

Don’t ask me why, but rewatching James Veitch’s comedy works like a charm for me… or maybe it’s my ritual hexpresso kicking in? Which reminds me: have rituals!

Stay in the zone

Under no circumstances should you let your first words after a grumpy interaction (or waking up) be on stage. One of the worst talks I ever gave happened when I took the stage after a charlatan. Full of righteous fury at his butchery of machine learning, I was so distracted that I proceeded to bomb my own talk.

Now I make a point of not listening until it’s my turn to walk on. I stick to my rituals. If I have to be in the room, I’m skulking in a corner listening to music in my barely visible headphones. Otherwise, I’m in the speaker lounge (if you want to fit in with the pros, you’ll refer to it as the “green room”).

Don’t cut time between talks so fine that you can’t take a moment to get back in the zone if you’re ambushed by one of life’s lemons on the way. Take the time to warm up!

Pause and breathe

A quick fix for a voice humans find unpleasant (nasal, high pitched, etc.) is using more breath. It also helps calm your nerves. So, breathe! And here’s a secret all the pros know: pauses feel much longer to the speaker than to the audience. Take pauses freely, but don’t fill them with ums.

Captain Obvious

Speaking of ums, it’s best to, like, practice speaking without, like, fillers. Ask your friends to call you out on it. (Mine are helping me kill an excess of “so” and “now” these days; no one’s perfect.)

The worst kind of filler is the arrogant variety: “obviously”, “naturally”, and so on. Drop these — they make you sound like a jerk. It’s always better to assume your audience knows nothing and hedge with witty ways of saying what you think is obvious. Remember, just about everything stand-up comedians say is also obvious, but people still love it for the wit and delivery. Borrow that technique for your 2+2=4. Trust me, there’s almost always someone in the room for whom it’s not obvious. Don’t alienate those folks. In my experience, people who are in favor of looking smart at the expense of others tend to be suffering from especially virulent impostor syndrome. Don’t be one of them and don’t let them bring you down. Keep it simple, get to the point, and drive your message home!

Quiet or loud?

Speaking quietly and slowly captures attention and tricks the audience into leaning forward to hang on your every word. Balance that against the boost in cheer and audience energy from speaking faster and louder. There’s no single right way, just try to be intentional about your style. Work with your vocal cords, not against them.

Practical details

Minimum expectations

All speakers are expected to know how to move on a stage and how to use standard mics, so practice before you have to give a talk that matters.

Find an opportunity to practice using each of the default mic types: handheld, headset, and lavalier (“lav” for short, also known as a lapel mic). Showing up unprepared to handle any of these is unprofessional. If you know there’s a good reason you won’t be able to use them, let conference organizers know in advance.

Costume design

“Wear whatever you’re most comfortable in” is just plain bad advice. There’s a good reason speakers rarely wear pajamas or yoga pants to the stage. Your clothes speak for you and should be selected to support your brand and message.

When you take to the stage, your audience will examine every detail the way they examine a painting — as if it’s there to signify something. For better or worse, clothes serve as visual symbols, so it’s worth thinking about what your clothes are saying as the latest sentence in humanity’s very long visual conversation.

“The detail is unyielding.” — poem by Szymborska

Low necklines mean something, as do epaulettes, hats, and everything else. In the west, the way to say “nothing to see here” in that visual language (for all genders) is to wear a well-cut buttoned shirt, flat closed shoes, and long grey/dark business trousers. Everything else says something — be sure you like what it’s saying and ask for advice if visual language is not your strong, ahem, suit.

If you pick a chunky bracelet or a tie with cartoon characters, your audience will devote brainpower to pondering their meaning and appropriateness. Be sure that’s what you want. Fashion statements are great when you’re intentionally making a statement. But theatre rules apply: if the item isn’t appropriate to the role you’re playing (in this case, your personal brand), leave it behind. For example, I’ve seen very few situations where shorts would have been consistent with the setting and personal brand of the speaker.

As long as you pick items that your personal brand dictates for the setting, everything will be fine. You don’t have to wear what everyone else wears, I sure don’t. Instead, imagine that a flattering movie will be made about your life one day. What would that movie’s (very competent) costume designer prescribe if told the scene and a description of your personal brand? Wear that.

Impractical details make you look bad

The last thing you want your clothing saying about you is that you were unprepared for the stage or that you’re impractical. Here are a few mistakes I’ve seen frequently.

Mistake 1: Nowhere to hang a lav mic’s heavy battery pack. The conference doesn’t pick your clothes for you, so they’re not responsible for your outfit being stage-compatible and working with standard kit. That’s on you. Check that your waistband can hold the weight of a can of beans, especially if it’s elastic. No waistband? Try a belt or sturdy pockets. None of the above? A special mic belt or armband or lanyard might be worth incorporating into your outfit.

Mistake 2: Silly shoes. If you’re planning on any amount of standing, I suggest you ditch any pair you haven’t walked two miles in. Watch out for blisters, slippery soles, and squeaking. Also, be sure you can put your full weight on the heels — if you can’t lift your toes and walk across the room, the shoes will only make you look bad on stage.

Mistake 3: Mic-incompatible collar and jewelry. The lav mic will be clipped at or just below the collarbone (not on the neck under the chin!), so high collar options like turtlenecks tend not to work. Saggy or wispy fabric can let you down as well, as can noisy jewelry. For example, if your earrings double as wind chimes, leave them at home.

The safest choice is a buttoned shirt or t-shirt. I imagine the Elizabethan ruff is among an A/V crew’s worst nightmares.

A/V crews have nightmares in which you turn up dressed like this and then tell them it’s their fault their mics don’t work with your outfit. You’re the costume designer, design smartly so your gear works with standard kit.

Alternatively, ask for a headset mic, which is like a lav mic that works with all collars (no need to practice) and has the bonus of tousling your hair. Bring a comb!

Mistake 4: Sweaty fabric. Some fabrics show wetness remarkably well. Grey cotton t-shirts are a cruel trap for the unsuspecting! Instead of relying on not sweating when the room is heated to a million degrees, check how the garment holds up when you pour a few drops of water on it.

Mistake 5: Not planning to be seated. Always check you like the look of your garment in its seated form and that sitting doesn’t uncover parts of you that your personal brand prefers covered. When it comes to trousers, don’t forget that they will reveal your mismatched socks when you sit. Have a seat in front of the mirror before stepping out.

Mistake 6: Forgetting air conditioning. When you’re cold, your body language says you’re nervous. It’s important to bring something warm along even when presenting in tropical places.


Stage lighting is a thing. If you’re giving a talk on a big, custom-lit stage, you need to think about makeup. If you usually wear it, apply it on the more intense side since it always looks less bold on camera and stage. If you don’t typically opt for makeup — and I’m talking to all genders here — consider powder and blush on stage if you don’t want to look washed out. If you’re speaking on a large stage, ask the organizers whether makeup is provided.

Equipment you must bring

Watch: Have a digital watch in case the conference’s clock isn’t working. A professional speaker ends their talk on time.

Clicker: Even though most conferences do provide clickers to advance your slides, bring your own clicker just in case. You’re a grownup now, please don’t advance your slides by pressing the arrow keys on your laptop. If you’re using the conference’s clicker, always ask the organizer whether it has a demonic little feature which I like to call “the ejector seat button” for instantly shutting down your presentation. Luckily, this gem of engineering is a rare one, but if you speak frequently, you’ll encounter it. Oh, and while we’re on the topic of clickers… do not press the clicker until you see your title slide. Conferences sometimes do a screen switch between walk-on screen and your slides, so you’re in danger of starting mid-deck if you do that.

Laptop and charger: Even if you’ve sent in your slides. Be disaster-proof.

Speaker emergency kit: Keep a packed kit with a threaded needle, nasal decongestant, throat lozenges, headache pills, band-aids, and whatever other things (medical/hygiene/beauty supplies, props, snacks for blood-sugar) help disaster-proof you. A friend tried to sneak magnesium fire starters into mine once. What are friends for, right?

Noise-cancelling headphones: Many conferences play adrenaline-inducing music to get the audience pumped up, but if you’re already caffeinated to the moon, that atmosphere is likely to give you unbearable jitters even if you’re a pro. You need the option of an antidote.

Equipment you might need

Mic belt / armband / lanyard: Since you — not the conference — are responsible for your costume design, ensure your costume works with standard hardware. Your outfit must have a place to clip the heavy lavalier mic battery pack. If it doesn’t, fix that by adding something like a mic belt.

Water bottle: If your mouth ever goes dry, bring water on stage with you.

Display adaptor: It’s nice not to have to be at the mercy of the conference having whatever obscure widget is needed to get your particular laptop to talk to their projector.

Hope you found that useful, speakers! It’s really not too mysterious — just remember it’s theatre and you’re cast in your personal brand. Stay true to that and have the practical details ironed out, then all will go swimmingly.

Good luck, thespians. Break a leg!

Here are some public-speaking masterclass guides I wrote to help you through more niche situations:

And now for something completely different!

If you had fun here and you’re curious about AI but you find most courses boring or beginner-unfriendly, here’s a snarky little something I made for you:

Course link:

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Cassie Kozyrkov

Chief Decision Scientist, Google. ❤️ Stats, ML/AI, data, puns, art, theatre, decision science. All views are my own.