You must rehearse in order to give a good presentation.  If you don’t rehearse, your body language will give you away.  Your body will say to the audience, this person is going through this experience for the first time, and that won’t look particularly competent. 

I’ve written another series of blogs on how to rehearse, so I won’t go into that here.  I’ll talk instead about why you must rehearse. 

I hear from busy executives all the time that they don’t want to rehearse because it will make them stale, or they’ll bore themselves and the audience, or other such faux concerns.  Interestingly, I never get those excuses from the professional speakers we work with.  They’re always ready to rehearse because they know it makes the difference between exuding confidence and competence – and not. 

Smart speakers will rehearse a speech they’ve given a thousand times before because it’s a new audience, a new venue, or simply a sound system they want to check out. 

The point is, audiences like surprises, but speakers don’t – or shouldn’t.  I have a rule of threes for this:  I can always tell a speaker that’s under-rehearsed because by the time the third unexpected thing happens, the speaker begins to melt down.  Let’s say the room is not quite the layout the speaker expected.  OK, he makes mental adjustments, then soldiers on.  But then the A/V equipment isn’t working properly, and the speaker and the sound people have to make some quick adjustments on the fly. 

The speaker takes a deep breath; he is beginning to get flustered, but on with the show, right? 

Then, his opening joke falls flat, and it’s Armageddon.  Too many things have gone wrong; his mental capacity is overwhelmed, and the speaker has his tail between his legs from then on.  The audience senses difficulty and radiates concern back to the speaker.  It’s a downward spiral that few pull themselves out of, even experienced speakers. 

Don’t let that happen to you.  Rehearse the speech, even if you’ve given it before.  Check out the room, and have a sound and equipment check.  Do all this the day before, or at least a few hours before, so that you have time to fix anything that’s wrong.  You, your body language, and the audience will all benefit enormously.