Kick butt on any standardized tests and try to get into the very top percentiles.
Do lots of extracurricular work, and volunteer... teach... that sort of thing looks really good.
Go speak to the registrars directly. Let them get to know your face. Bring them chocolate!
Get on their good side, and try to get some insider information... hints/tips and the like.
Play up your strong points, and play down your weaknesses (i.e. don't adverstise too willingly, unless asked directly, that you failed physics... that sort of thing).
Off the top of my head, that's all I've got. That, and well wishes.
Good luck arkain!
