Hi there. Nice to here someone else with great enthusiasm for the Air Force! I've just completed OASC (Before Christmas) and have been offered a place on No. 197 IOT course, as a pilot. If you want any gen at all about the selection procedure please don't hesitate to email me (there's a button at the top of this reply) and I can answer whatever queries you may have. If this is not possible, however, I would offer you three main bits of advice:
1) As TopGun already stated, don't try to be someone else, DO NOT try to guess the 'correct' answers in the interview. There aren't any. I fluffed a few and I was still selected so don't flap if you screw some up
2) Don't worry about being nervous. Do your best to relax but don't be cocky. They will expect a certain amount of nervousness. Everybody is, I know I was, it will pass once you get into things
3) Once you get through to phase 2 relax and enjoy yourself. You will find it tough but remember: they've been doing this for years, and if you've got the right stuff, they WILL see it. There's nothing you can do to change things now, just go out and perform to 100%
Oh, and try not to drink too much in the bar in the evenings!
All the best
-Dukeyboy