I get very nervous on stage. how to stop this?

Very normal: Nervousness on stage ("stage fright") is a COMPLETELY NORMAL reaction. I have had many performers as patients when I was in Primary Care and many of them felt that they actually performed more successfully when they had this anxiety. In severe cases if your blood pressure and heart are normal a small dose of Inderal (propranolol) (propranalol) may help. Talk to your Primary Care Doc

Common: First, this is common and is under your control. Second, really good preparation for the role, speech or other activity will make you much surer of yourself and in control of the situation. Last, pushing yourself to appear again and even again will strengthen your self image and resolve and you can learn and be more poised.

Best bet is: to seek professional help, as formal therapy or even medications may be right for you. Otherwise focus on being prepared, be positive, avoid self-doubt, practice some form of relaxtion like mediation/relaxation response/prayer, and don't forget to live healthy(that includes eating and sleeping well and being active). Good luck.