When setting a magical apparatus (such as a wand or other item) on your magic table use the arm that is away from the audience. You never want to cross your arm in front of your body when placing things on your table.
Keep your body in full view of the audience lest they think you are trying to hide something.
Learn to stand in one place without having to spread your legs apart. It is all right to do this rarely but to continually do this is not good. Standing properly is a tough thing. Any good book on acting can teach you more. Go to your library. There are some excellent works on this subject.
Be at ease but never overdo this. Always know that you have people watching you. Don’t pick your nose in public or dig wax out of your ear. I’m serious, I have seen this done by those who should know better.
Always talk to the lady in the back. In other words, make sure everyone hears you.
At the finish of a trick, hold the finish so that the audience knows the trick is over. Too many performers don’t “hold and pose” the climax. If you have just found the selected card, then hold it high so that everyone can see it. Stand still until they applaud. Then you can put the thing away.
If you are using a green handkerchief, please show it. Make a gesture that something is about to be done with this item and that they notice it is green. Remember that an audience won’t know that a red handkerchief used to be green unless they notice it was green in the first place.