Rules from Edward Tufte for better presentations.

Show up early: Something good is bound to happen.
Lay out the problem: who cares about it and what the solution is.
When presenting complicated material, follow PGP (particular/general/particular). When you talk, TALK: avoid the obvious reliance on notes.
Give everyone in your audience a piece of paper.
Match the information density in your presentation to the highest resolution newspapers. Avoid overhead projectors. Keep the lights up in the room.
Never apologize.
Use humor, but make it relevant and never irritating.
Use gender-neutral speech.
Practice intensely beforehand.
Meetings have a very low rate of information transfer.
Take questions, but NEVER condescend to the questioner.
Keep in mind that most questions arise from personal concerns.
Express enthusiasm about your material, but only if your enthusiasm is real.
Finish early.