R. Todd Stephens has a good list of public speaking tips. (I'm linking to the Internet Archive's version of this page, as it's no longer available on Todd's site, and reproducing the entire list below.) I particularly like his last tip:
R. Todd Stephens' Top Twelve Speaking Tips
Practice, Practice, PracticeThere is no substitute for this. Every professional speaker spends an enormous amount of time working out the session. “It takes me three weeks to put together a good impromptu speech." - Mark Twain. Practice at home, in the car, in the office, 5-10, 20, minutes; what ever you can schedule.
Establish that Foundation
The first 10 minutes may be the most crucial time in an entire speech. This is where people form perceptions on your skills, knowledge, and experience. Delivering a solid performance here and you will set the stage for the remainder of the session.Flexible Ending
No matter how much you practice, you will approach the ending of your session at different times. Try to take the last 10 minutes and make a mental note of which slide you should be on. Assuming you have 20 slides and you think you should be on slide 16 with 10 minutes to go. You should be able to expand the discussion points to 15-20 minutes or shrink this time period to 5 minutes or less. This is crucial to deliver a professional speech; attendees don’t want to feel cheated by ending early or not covering some of the material because of time constraints. Your ability to pull this off without giving a hint of what’s going on will set you apart.Limit the Use of Bullets
Most speakers like to use bullets in their slides and the more the merrier. The problem is that you can’t really tell where you are in the slide deck without reading the slide itself. Try to place diagrams or even clipart into the deck that can remind you of where your are. Most nervous conditions come during the transition period between slides and by using diagrams you only need a glance to determine where you are.Deliver with Feeling
The basic difference between the good, the bad, and the ugly is passion. Deliver the session like you have spent your entire life waiting for this moment. Deliver the session with feeling and emotion, let your passion flow like a Baptist Preacher, can you say amen?Watch that Slide Count
You should be able to spend 3-5 minutes on each slide besides the title and support slides (QA, References, Contact). Why not less than that? Because some members will be reading the slides while you talk and you want to make sure they can read the entire content. Hence, why you shouldn’t put 20 bullet points and then cover in 2 minutes. Why not more than 5? Perhaps you have too much content that could be much easier explained in separate slides.Alter your speed of delivery
If you ever watch the World Poker Tour, you will hear them talk about changing the speeds of play. Playing fast, slow, conservative, aggressive, etc is the recipe for success. Same holds true in speaking, delivering a slow monotone for the full period can lull the audience to sleep. However, an overly aggressive style, like Richard Simmons, can wear the audience down and perhaps lose the message in the process. Vary everything!Use Humor or Interesting Things in the Show (It is a Show by the way)If you have ever watched Emeril Live more than once you will pick up on some comments that are meant to interject humor and delineate him from other cooking show hosts: Bam, Use your Knobs, Kick it up a Notch, Smell-a-Vision, etc. They are funny fillers that have become a brand unto them selves. Work on a few things that you like to say besides Hmmmmm. Props are good for this….
80-90 Percent Rule
No matter how hard you practice, when the day comes you will only be able to deliver 80-90 percent of your ability. The same is true for professional sports like golf. The pressure, time constraints, public view, and a variety of other reasons cause you to be less than perfect. It’s ok, most people won’t notice.A Built-in Support Group
Remember, the attendees have selected your session to attend. They may have paid to see your presentation and you can bet they want to see you succeed. Nobody goes out and buys a car in hopes that it will break down or get into a wreck. Go on, everyone wants you to succeed.The Room is your Friend
Most speakers find a parking spot at about 35 degrees to the left and right of the screen. It gives them comfort of being able to look at the screen at any point in time. Don’t park the car, ride that baby. Walk in front of the screen (just don’t park there), walk in the isles, walk down the sides, vary everything. This allows you to look directly at the majority of the audience, since most people sit in the back of the room. Also, big secret time. The most important time you need to see the screen is when you change slides, this is where you gather your thoughts. If you time it right, by walking back toward the front of the room you can see the entire slide without appearing as you needed it.Be a Host not a Speaker
Before the session, try to meet as many people as you can. Even if you only talk to the people you know, others will get the feeling that you are an approachable person. Try not to spend more than 2-3 minutes with any one person; bounce around. If your session is large, you may only get to say hello with 5-10 people, but these folks could be your supporters that you focus on during the session.