Just as we all have unique ways of walking, dressing, and talking, we also have a unique style of delivery. Videotape yourself giving a speech and look at how you delivered it. Look at four television interviewers with essentially the same job and see the huge differences in style: Oprah Winfrey, Barbara Walters, Charlie Rose, and Larry King all shape their shows around their personal styles.
The key to developing that style is to recognize your strengths and build on them. If you are a born raconteur, incorporate stories in your speeches. If you keep your friends amused and attentive with lively facial expressions and hand gestures, don't cut them out of your speech. Too much style can be distracting, and some speakers mistake it for substance. I am a very animated speaker and am aware that I sometimes have to tone down my gestures and movements. But for the most part, if you take advantage of your own natural style, it will enhance your relationship with your audience.