I got this from a book on singing by Mark Baxter. Seems like it might be some good advice for lots of different performance situations like presentations etc. not just for singing so I decided to post it in case it might help someone. I haven't really had the opportunity to try any of it out yet.
If you've ever been overwhelmed about the thought of baring it all in front of an audience - take heart you're in good company. Whether they admit it or not, every performer has dealt with stage fright at one time or another. However, the important difference between the pros and everyone else is that the fear did not stop them from performing. The knowledge that you can do something regardless of how you feel is your best weapon against stage fright.
ATTACK THE PHYSICAL SIDE FIRST
The fear of performing may begin in your mind, but the physical reactions are what cause the problems. Remember, you can attack an anxiety either physically or mentally; I feel it's easier to work with your body, the physical.
When you feel the first signs of panic, head immediately for your warm-up routine, breathing exercises or non-vocal work out. Get your body busy before it has a chance to react to your thoughts. Trying to think things out will only allow your body to tense before you sing. It's counter-productive to try to stay calm, so use your nervous energy to your advantage.
Any exercise mentioned in this book will do the job. Focus on your physical form rather than the sound of your voice. The point is to distract your muscles from the anxiety. If you rush the workout, you will place more emphasis on your fear, and the purpose of exercising will be lost. Breathing exercises will get to the heart of the matter the quickest. The first area affected when panic strikes is your breath. Deliberately returning it to a natural state will calm your mind.
FEAR OF THE UNKNOWN
On the mental side, the anxiety built over an upcoming performance is based on a fear of the unknown. Let's say you have an audition tomorrow and you start to wonder about the outcome, or you wonder how the crowd will react at your first gig with the new band. Since the outcome of any future event is unknown, your imagination takes over. This is when your personality type take over.
If you're an optimist, you'll imagine the audition of the gig being tremendously successful However, the pessimist will predict anything from small problems to catastrophes and then start to sweat about them. Pretending to be an optimist when you're not is useless. You can't fool yourself. The only weapon a pessimist has against his imagination is the truth, otherwise known as current reality.
If you find yourself in the grips of self-doubt, start making statements about things you know to be absolutely true. Keep them simple at first, begin with your name, age, date and time of day. It may sound silly, but I've seen people unable to recall how old they were or what day it was while in a panic over an up-coming audition. These basic facts help to ground your mind to the present. Once you're through the easy stuff, start making statements about what you know to be true about yourself. No opinions allowed - just facts about how long you've been singing, why you started and why you enjoy it. Don't forget that you started singing for the fun of it, so try to keep it that way.
FOCUS ON A GOAL
Once you've brought yourself back to the here-and-now, set your sights on a goal which would make the event a win. Don't give away your power by letting others deicide your success. You can't make people like your voice, so wishing for applause puts your fate in the hands of the audience. A more constructive goal would be to sing your best and then take steps to insure your success. I guarantee that when you achieve this goal, you'll hear the applause of your dreams.
Rehearsing, working out and vocalizing are all active steps which provide you with confidence and control. It's important to act on things you have the power to change and disregard the rest. Focusing on things beyond your control makes you powerless. The level of anxiety you experience before a show is determined by your concern for the unknown circumstances. Confidence only arrives with preparation.