When I used to teach presentation skills, the question of nerves came up all the time. So I will explain my advice to them.
1) First examine the reason for the nerves, Fear of failure and losing face in front of peers is one factor. Practise and practise will reduce this factor but can never (IMHO) eliminate it completely, the fear gives us the edge otherwise we could become [censored] and sloppy. Fear of being ill prepared is a planning issue. In a non professional format a simple decline to perform can suffice otherwise plan ahead and practices.
2) Know your subject, once again the practise will help you in this but its not just the items you perform, the more knowledge you have the more tools you will have available to you. Mistakes dont happen they are caused, examine why you think this happened and learn from the mistakes. The mechanics of the effect should be second nature and natural, allowing you to focus on the audience.
3) Plan for all issues, again practise and knowledge will cover this tip, but examine the items you perform and think about what can go wrong. For example if the spectator turns their hand around to show in fact they are holding 2 sponge balls not just one.
4) Present your self professionally throughout, you can relate this to magic by saying never admit its gone wrong, the audience dont know what is going to happen so (dare I say) lie to them, waffle them, try to recover from it and if all else fails laugh it off. Never react to a mistake, and in the beginning never turn down a chance to perform, you will learn from a 2 min performance to a real live person than years with a web cam or mirror.
Good luck and keep performing, magic is a performance art, keep on going and practise some more.
Some advice the Late Ken Little give me some years ago, when I was asking him about stage fright, he said start walking towards the stage before your name is called, Ive used this since and it seems to work, for close up dont allow your self to ponder on the event as all the pre-planning and pre-practise will pay off. Also have a post performance post mortem, make sure you learn the lessons each performance offers, if we keep learning magic will only get better, its when we think we know it all will magic suffer.
Saying that I sit my Magic circle exam soon and will be a bag of nerves, performing for magicians has to be the worse thing ever, however I taking my own advice and the advice I have been given by many close friends. Just thought I would explain Barry the nerves will never go completely, you just need to use that fear as energy to improve and learn from mistakes and try not to repeat them. Now Im off for another sleepless night of worry. :help: