Are you just a little bummed out by your last presentation? Do you think you didn't do nearly as well as you could have? Perhaps you stumbled over your words, lost your place or your train of thought at one point. Maybe you got a little flustered when something didn't go exactly as planned. Well, don't worry about it. Little bloopers happen even to the absolute best presenters. Watch this video of Steve Jobs' various keynote imperfections over the years on the Tauquil.com website. Proof that even the best are not perfect.
No matter how good of a presenter you are, you will occasionally stumble over your words. You're human, after all. And regardless of how reliable you think your technology is, at some point it will fail you. Technology fails usually immediately after you praise its virtues to the audience: "You're going to love this new feature, ladies and gentlemen. Take a look at this new...um...<oh crap>...." We've all been there.
We strive for the perfect presentation, the perfect pitch. It is unobtainable. Yet, it is the small imperfections that make us human. It is the small imperfections that make it real. Still worried about not being perfect? You may enjoy, then, this helpful book, The Art of Imperfection.
In future I'll tell you my secret for backing up important presentations while traveling light on the road; kind of a "belt-with-suspenders" approach.