Kateřina Jagla gives a lecture on self-confidence and discusses numerous questions how to overcome stage fright and gain more self-confidence as a musician. She says that it is very important to understand the reason why we are playing music instrument. Ask yourself and try to find answer. When we are dealing with stage fright ask yourself what would really happen in case you fail.
She emphasizes that it is also very important to be mindful and be aware about your thoughts specially at the moment when you feel anxious. Try to figure out which thoughts makes you feel anxios.