I don't know exactly what your background/experience is, but experience in sales will give you good, everyday practice interacting with other people and demonst

I don't know exactly what your background/experience is, but experience in sales will give you good, everyday practice interacting with other people and demonstrating on the fly. Like mixmax said, watch for Steve Jobs' presentations. He has a strange personality but his stage presence is outstanding. How to win friend and influence people (Dale Carnegie) is also really good. I would avoid most of the current "sales/presentation" self-help books out there. Most of them are not worth the paper they're printed on. One last thought, try and find a mentor or a coach and/or join a speaking club. Toastmasters (http://www.toastmasters.org/ http://www.toastmasters.org/) and the National Speakers Association (http://www.nsaspeaker.org/ http://www.nsaspeaker.org/) are good, but they may be overkill if you don't do demonstrations regularly or to larger audiences.