One way to become a better presenter is by watching yourself. The easiest way to do this is by using a video camera and recording your presentations. I highly recommend that you make video critiques an ongoing practice. They will prove to be extremely helpful because you will quickly discover the good, the bad, and the ugly about the way you present. Remember, when you critique yourself, it is imperative that you notice your strengths and not just your weaknesses. Spend at least as much time developing the things you do well as you do shoring up the things you need to improve.