Don't take it too seriously- go in with the attitude that it's not the end of the world if you don't get a bid, and you'll be much more relaxed.

Don't bring up the fact that you've rushed before. If they bring it up, don't deny it, but don't go broadcasting it.

Try to avoid the "so what year are you" questions. Talk about your major, your other involvement, what you want to be "when you grow up" etc. I found that most of the time the "so, are you a freshman" didn't even come up. Again, don't deny it, but don't broadcast it either.