how to develop presentation skills and be a successful speaker

The best thing you can do to be a successful speaker is that you will put yourself as a audience or listener. Put yourself in their shoes, that way you can convey your ideas well. Successful speakers dont use high level words, instead they use a common language which they can be easily understood. Mastery or knowledge of your topic is important also, it can make you confident as you speak infront of people. Be confident as you speak, speak as if you are the author of a book, but remember make it simple as it can be. The main purpose why you speak infront of people is to convey or share your ideas, so dont miss that chance.

I think the best idea is to video-tape yourself while giving a presentation. Then watch the tape and make note of what you did right and what you did wrong. It's pretty much like seeing yourself through the eyes of your audience. Using this method I found I looked too much at my notes, when I needed to make eye contact with my public instead. Also, somebody told me I put too much text on my slides; I took that comment into account, and I'd say my presentations are now better and more focused.