Audition tips for freshman who wants to impress?

I'm going to be a freshman in high school in the fall, and can't wait to try out for the fall play. However, I am kinda freaked out. Our high school has an awesome drama program and I can't wait to be a part of it, but I'm afraid that I won't get a part :( There is a lot of talent leaving this year so my chances are greater for getting a bigger part. I know that freshman rarely get roles, so I really want to impress them. Any tips for the underdog? Oh, I'm a girl by the way. Lol I don't know if that matters but whatever... thanks (: