The first impression that you make upon your audition judges will be a visual one. Dress nicely in an outfit that compliments your body shape. Refrain from wearing jeans, shorts, tank tops or other extremely casual types of clothes. You shouldn't dress as if you were going to a formal event, either. Business casual is usually acceptable for most auditions. If you're auditioning for a theatrical role, you can hint at the role with your clothing, but don't overdo it. For instance, if you're trying out for a role as a biker, you might pair a black leather jacket with a nice shirt and pants. Make sure your hair is neatly groomed and your makeup is tasteful. Wear comfortable shoes, but avoid flip-flops and other shoes that are overly casual.
Your audition should communicate that you know your part thoroughly and have practiced it well. Forgetting lyrics to a song or lines to a play can sink your chances almost immediately. Devote the time that it takes to memorizing your audition part beforehand. Become so comfortable with your part that you can retrieve it easily and without error. When you show the audition judges that you have a firm grasp on the tryout piece, you also communicate that you will be dependable in terms of working hard to accomplish whatever is required of you. If you don't know your part, you send out a message of being amateurish and unreliable.
One of the strongest selling points of a person's audition is his confidence level. Confidence allows a person to project charisma, which can woo over audition judges. Confidence says that you know what you are doing is high quality and that others should think so as well.
There are many ways to project confidence. Stand upright with your hands by your sides (unless you're holding a microphone). Do not slump your shoulders. Refrain from nervous mannerisms such as shifting your weight back and forth on your feet or playing with your hair. Use a clear, appropriately loud, strong voice. Make eye contact with the audition judges. Be polite in any verbal exchanges you may have with them. Never apologize or make excuses for not performing up to the level that you wanted. Even if you think you may have made a minor mistake, act as if it were the best performance ever. Your confidence may smooth over any minor rough edges in your performance.