"Be sincere, be brief, be seated."

Could this be public speaking's very best advice? These words were Franklin D Roosevelt's advice to his son on how to make a public speech. But is this public speaking advice really good for a public speaker seeking an impact...?

At a recent networking event, I was pleasantly surprised to see how the sponsor managed his appointed moment in the spotlight. He stood up, he built rapport with the audience, he said a few brief things about his business that more or less related to us in the room and then he finished. He followed Franklin D. Roosevelt's advice of "Be sincere. Be brief. Be seated" to the letter.

It was a pleasant experience and the audience thanked him for it. But it got me thinking. If we're really aiming to make an impact as speakers, is this the best way to do it? As with most things, I suspect there's a balance.

In the brief corner...

• Brevity is a sure-fire way to make sure you remember what you say. Just a few lines are easy enough for most of us, even if the event we're speaking at includes a free drink or two.
• You can guarantee you won't lose your audience's attention - they simply won't have time to drift off to studying the ceiling, an attractive audience member, or their iPhone. Most business audiences spend far too much time listening to irrelevant, flabby presentations, so brevity brings a welcome change.
• Your audience will be more likely to remember a brief message. One clear message stands out in a sea of tens of complex messages, so provided that your message is simple and relevant to them, it will be remembered as an integral part of the event.
• You'll be popular. Most public speaking still feels like a school lecture and - let's face it - most of us prefer talking to listening, especially when there's food and wine about.

In the lengthy corner...

There's something nagging at me that tells me brevity may be an excuse. Is it always the case that short is sweet and lengthy means losing the audience? What may be hiding underneath the apparent crowd-winning approach of brevity may be one of the following attitudes:

• "I don't want to have to prepare - I don't have the time"
• "I don't want to 'trouble' the audience"
• "I'm shy or embarrassed about my message"
• "I don't know how to wow a crowd - better not risk it."

When I dig into these sorts of attitudes with clients, we normally find that it comes down to self-confidence. Many people are in some way shy of taking up space - of intruding into other people's consciousness. They're shy of being seen and heard, in case someone doesn't approve of them or their message. We prefer anonymity to the risk of the spotlight. Advice like "it's better to remain silent and be thought a fool than to speak out and remove all doubt" doesn't help much. And the fact that we're not sure what to say, or how to say it, only compounds the trouble.

Then there are the 'rational' excuses for brevity, like not having enough time to prepare. Let's deal with this one. If you have a platform to speak to people from, you have probably the most valuable opportunity to influence or inspire those people. If you are honest with yourself, whatever else you're busy with is probably less important than getting your message out there in the world. It's easy to avoid finding time to prepare your public speaking, because nobody's forcing you to do it well, everyone else may have set the bar low in terms of the general standard and you don't have a client paying money for it. But this is free marketing that, if done well, will hold you in the minds of your audience for weeks, or years to come.

So where do we land?

THIS public speaking advice is NOT pointing to lengthiness for the sake of it. I don't intend to encourage speakers to fill more space just because they can. We all know where that leads... But if you consider your reasons for being brief, perhaps you might find that brevity is not necessarily the best solution. You may decide that the best solution for you is to step boldly into the limelight and stay there for as long as it takes to make your message heard. And how do you guarantee that this will be more powerful than the short-and-snappy approach?

1) Find and focus on a key message

Deliver that message in the most economical way possible, but do deliver the message. Put your full power behind it. Too little time spent reinforcing the message means it will be lost - too long means the audience will be bored or outraged. But you will usually have a lot longer than you think before the audience get fidgety. Stick it out, even if you feel uncomfortable.

2) Check how the audience feels

You can see if your audience are still with you from where their eyes are. If they're looking at you with shiny eyes, you have their attention and they want more. Give them more. If you can't see any eyes at all, then wrap up quickly.

3) Be relevant

Neuroscience shows that people retain knowledge under two conditions. The first is that they see your information as relevant to them. So make sure that your message fits with and relates to your audience. Don't necessarily expect them to see the relevance instantly - you've thought a lot more about your subject than they have. To help them see the relevance, use juicy stories, anecdotes, quotes and visuals that help them to understand your point.

4) Be unique

The second condition for retaining knowledge is that the situation is unique. Here's where the fun bit comes in. If you want your audience to remember you, you'll need to do something a little different from the rest (whilst - please - making sure that whatever it is is still relevant to your message). The same old powerpoint, the same old format and the same old cliched phrases will not be needed here.You're looking to add the sparkle I call 'Freshness'.

Get your audience involved, show them a unique prop that represent your message, tell a story they can't forget. These are all parts of your public speaking that will take up time, but they will take up time in the right way, by reinforcing your message.

5) Be brave

To carry it off, you need to step beyond your comfort zone, so be brave! An audience are naturally more confident in a speaker who appears confident his/herself, so let confidence shine out, even if you don't see it.By pushing through your boundaries, you'll find yourself speaking for a little longer, taking up just a little more of the audience's time - and being a more memorable and powerful speaker as a result. Good luck.

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