Relax! Most actors mess up their audition because they over-think or are nervous. Or get so nervous they start to over-think.
Trust yourself and the work you've done in preparation for the audition.
SO many things go into casting an actor for the role. Use the audition as a time to act, have fun and establish a relationship with the Casting Director. If you get a callback or book the role then that is a bonus.
Realize that a career as an actor is a long, long road. Be patient and enjoy it.
