How do I show up the stable snob at a show tomorrow?

I know, I know. I should just be going to have fun and do my best, not to show anyone up, and I am, but oh my God, you have not seen how arrogant this girl is. She thinks she is soooo much better than everyone and refuses to associate herself with "average" riders. I won't fret if I lose to her, and I know I will, but it would be fantastic if a beginner (started riding in December) like me beat a self-proclaimed expert like her. And she is good. I know expecting to beat her in this millennia is unreal, but do you have any tips that could help me? I do have one advantage: my horse knows mais than hers. Assuming I knew what I was doing, I could beat her in jumping, dressage, and Western adestramento (as if she'd ride like a "hick" in Western), but I don't. I'm still in the cabeçada and walk/trot classes phase. Still, unrealistic or not, I'd like to win, not only to beat her no matter how fun that'd be, but to well, win. Like I said, I'll have a blast even if I take last in everything, but how she irks me, I'd enjoy beating her. Ideas?