I’m often asked how long a presentation should be. The answer is, unhelpfully, as long as it needs to be and as short as it can be. Each presentation and each audience is different. Each topic and each venue is different. There’s no one-size-fits-all. So here are some thoughts for figuring out how long is long enough…
For starters, think of how long you can work out at the gym. 45 minutes or so? An hour perhaps? After that, your muscles are so knackered you’re not using your time to best effect – you’re better off stopping, doing some stretches and then going on to do something else (like go back to work or go home :) ). Your brain (anyone’s brain) works the same way – there’s a very limited amount of time you can concentrate for, after which you might as well stop and do something else.
The trick lies in getting the key ‘stuff’ into the middle part of the presentation, when your audience’s ability to concentrate is at its highest.
But one of the big problems you’ll have, unfortunately, is judging how long your audience can concentrate for – because things are a lot easier for you, as the presenter. Firstly, you’ll be working less hard in some ways, because the material isn’t new to you – and secondly you’re likely to be boosted up a bit, energy-wise, by your nerves and so on. Combined, those things mean you can concentrate for longer than your audience – and you’ll have to compensate for that when you present. You can’t judge their level of knackeration by your own.
The simple fact is that you need to keep a weather-eye on how much energy your audience is showing. I know this sounds a bit woo-woo but even if they’re not moving you’ll now if they’re getting tiered if you’re looking for it. Trust me on this.
So what to do when that happens?
Hit the reset button. In an ideal world you’d have planned your presentation to have a natural break shortly before this point, but in case you haven’t, you have a few options. The first, of course, is to have a break in any case. I’ve never found an audience get upset when I’ve done this if I’ve introduced the break with an overt explanation of why I’m doing it, such as “The next bit is pretty tricky and we’re going to need to concentrate – shall we take a two minute break so we’re fresh for the hard bit?”
If breaks are out of the question, at the very least change medium. If you’re using PowerPoint, turn it black and just talk. Or move over to a flipchart… or something… anything to make the audience hit the mental ‘reset’ button. Group exercises might work, in desperation! ;) The key thing is to change things in such a radical way that it hits your audience’s “reset” button.
Sometimes all you need to do is swap sides of the stage, but other times you need to bring out the big guns and be very (very!) un-subtle about it.
Go for it.. hit the reset button every time you see your audience flag.