I recently took a course with boyscouts called NYLT, which stands for national youth leadership group; in short it was a bullstuff class just to certify I know my stuff as a leader. When it comes to a speech, don't look at the front row, look straight for a middle line. This make everyone feel like your watching them. Be careful with your hands. Don't play games with em, don't twiddle, don't stick them in your pockets, DO NOT PUT THEM IN FRONT OF YOUR JUNK, and overall don't let them be distracting. Also, don't dance around from foot to foot. Make your movement slow and in pace with your words. 3 words = 1 step, if you have a big stage at your disposal.
That's all I can think of, I'm sure you'll be great, just remember they want to be there just as much as you do; per se, they DON'T want to be there. Don't over complicate and don't dumb it down. Mid line.