How to Prep for a Presentation

In a conference spanning several days, know before the conference on which day and at what time you are speaking, and know when the social events are. If you are speaking on the last day, or after a social event, market your talk beforehand or you'll have a smaller audience.

Have a bottle of water on stage with you, not soda or coffee. If your talk lasts more than 20 minutes, believe me, you'll need a sip now and then. Taking a short break to drink is OK, you can use the silence to highlight the point you just made.

Speaking of silence, don't feel the need to talk all the time, use silences and pauses, it adds rhythm to your presentation. Don't forget you are the expert, the audience is not, they might need some time to digest the information you are giving.

As an expert, you might want to shove everything you know in your talk. Don't do that, ignore the smaller details and focus on the story. No one care about the small optimization you have spent a month tweaking (unless this is the topic of your talk). Focus on the broader picture.

That said, one key element is missing: the enthusiasm/delivery of the talk itself. What I mean is it's not enough to know the talk -- you also have to "know" the enthusiasm.

Personally, I think this is the hardest part, because enthusiasm is usually built up between people (as in you are talking to a friend, they get more excited, so do you, and each feeds off the other). When you present, there is no "other person" to feed off of, meaning you have to create that mood all by yourself. Presenters who do this are very desirable to listen to, regardless of what they're presenting.

However, I would only go through this amount of preparation for a really really important talk. I think 50% of this effort would lead to a talk that's 80% as good. Under most situations, I'd take this route.