Some things I've learnt about public speaking | John Graham-Cumming

In the past I've written a couple of blog posts titled Some things I've learnt about programming and Some things I've learnt about writing. People seem to have enjoyed those posts (judging by the page view counts and comments) and so I thought I'd write something about public speaking and specifically about conference speaking.

0. It really does help to know what you are talking about

If you know your subject well then you will be able to talk well within the limits of your knowledge and be interesting and informative. You'll also be more comfortable and your comfort will come across to the audience.

If, on the other hand, you are giving a talk about a subject you know little about you are likely to come across poorly. This is partly because you won't have confidence in what you are saying and partly because it helps to leave audience wanting more. Also, when you are ill informed it's easy to be repetitive and therefore tedious.

I like when there's a very restricted amount of time for the talk, it forces me to figure out what's interesting to say. It's good if I don't have enough time to say everything. I can always continue with a Q&A session, individual chats with audience members or a blog post.

A common mistake amongst speakers is trying to say too much. There's no need: be interesting and you'll get the opportunity to say much more at another time.

1. It really does help to practice

Last year I gave a TEDx talk titled The greatest machine that never was. It was about Charles Babbage's Analytical Engine. As a speaker you are under pressure at a TEDx event because the audience expects you to be interesting, and because the organizers keep to a rigid timetable.

One thing that made my talk enjoyable for the audience was that the organizers of that TEDx forced me to do the talk for them live beforehand. I had been dreading doing that, but it turned out to be key to making the talk flow smoothly. With the slides (which were mostly just single images) printed on paper, I ran through the talk and was able, instantly, to feel what did and did not work. It also helped to cement the flow of the talk in my mind.

And practicing also gave me the freedom to ad lib. On the day I said a few things that were not planned; I was able to do that because the rest of the talk was solid. An entirely ad libbed talk would likely have been tedious and made me seem erratic.

And now I make a point to practice, even if it's just me talking to the teddy.

2. It's good to tell stories

Even if you are giving a technical talk about the internals of the JVM stories help the audience. They provide a framework for the points you are making and they link slides together. Without a story talks can sometimes be a jarring sequence of slides with tenuous connections. Stories act as mental lubricant that helps keep your listeners' minds working.

At StrataConf London last year I gave a talk titled The Great Railway Caper: Big Data in 1955. The talk is intended to be about Big Data and helping to define what that term means (a rather boring topic). But the talk itself is entirely about the Lyons' Electronic Office and one particular program that was written for it in the 1950s. The story of that program tells a story about Big Data today.

And the LEO story starts with another short story. The introductory story is used to tell the audience what I'm going to talk about.

3. Unless you are fascinating don't talk about yourself

You probably aren't fascinating. And the audience probably doesn't care about you or what you've done. They care about your subject matter. It's rare that your subject matter will be you.

Imagine for a moment that you are Neil Armstrong. A talk by Armstrong about the experience of being on the Moon would be more interesting that a talk by Armstrong about himself.

And, ironically, the less you talk about yourself the more interesting you'll be and the more interested the audience will be in you.

4. Passion doesn't mean shouting at the audience

Genuine passion for a topic comes across effortlessly. Pick a subject you really care about and talk about that.

Sometimes you'll see a speaker faking passion by speaking emphatically and shouting at the audience. It's often a sign that they don't have much to say; that's probably why the emphatic, over-the-top style is so popular amongst 'motivational speakers'.

5. Watch yourself

I cringe every time I watch myself giving a talk, but it's important that I do.

When you watch yourself, you can see all the mistakes you make and the mannerisms you'd rather not know you have. You can then be mindful of those problems when you speak.

6. Don't waste words on a "Table of Contents"

If you have a story to guide your talk there's little point having any "table of contents" slides. They just bore the audience and provide an unnecessary structure. The real structure of your talk should be a narrative that leads the audience through your points. Listing the points may be useful as a summary, but I'd even be wary of that. Tell a good story and they'll remember what you said and think you're a great speaker.