I learned from a very seasoned speaker to nod while speaking. There’s something contagious about a nod. When you start to nod at positive points in your presentation others will match your nod and you’ll gain agreement from a wider range in your audience.
There are two schools of thought based on accessibility. There are some speakers who isolate themselves from their audience, but I believe the more available you are, the more impact you will make.
While speaking, do not hide behind the podium or table. Get right out there and be with your audience. After you’ve spoken, stay around so your audience can speak with you. If you’re at a trade show or doing a keynote at a convention, stay at the same hotel as the attendees. You’d be amazed at the good will it will create for you.
Always video tape every presentation you do. Use the video to review your presentations. What is working, what isn’t? You’d be amazed at what you can tell from the video. You’ll see what works, what doesn’t, your stories that get the best reactions and the ones that don’t work.