Giving talks
Some tips and tricks about giving talks:
1) Tell a story.
2) Think about what you want people to remember from your talk.
3) Don't overload your talk.
4) Be ready to be flexible with your timing.
Slide talks:
5) Try to keep the number of slides down, so you don't have to switch slides too often, as well as the amount of text on the slide. ---it is totally doable to give a 1 hour talk on less than 10 slides.
See also Dan Margalit's page on giving talks, with tips and tricks from many people.