Lucky for you I am a modern-day Casanova.
Here's my educated guess on what to say:
She accepts - "Cool. Pick you up around [time]?" (or if you don't have a ride, "Cool. Hope you like to walk!" :))
She rejects - "Oh, okay. I kind of thought you smelled funny anyway."
Seriously though, just be yourself. But not the self-hating you that shows up around here every now and again. Be the funny, ever-so-charming you.