How to take being rejected?

A general rule of thumb is that she doesn't immediatly say "yes" or one of it's variations ( yeah, of course, sure, great), then it is a rejection. Things such as "cool" and "uh-huh" means she'll go, but you weren't her first choice. "Okay" depends on if she says it happy-like or not, and "cool" and "uh-huh" can fall under this category as well. If she beats around the bush, it's a no.

If you are rejected, she's probably flattered but doesn't want to hurt your feelings. I would say, "That's okay, I'm just glad I asked you." And even if this happens, remeber it's just prom. I've been there and even though movies and tv build it up to be a huge thing, it's just another dance and there will be other dances and people in your life.

It's only going to be awkward if you make it awkward... but regardless, the only way to learn to handle being rejected is by being rejected. It sucks the first time, but it gets easier. I've admittedly been rejected several times. Like the old saying goes, "Try 1000, get 1"

She'll just say 'ah sorry, no' or something like that and you should just be really cool about it and act like your disappointed but don't get upset or mad about it in front of her either. Say something like 'ah okay, let me know if you change your mind.' Or something like that!