I can't really recommend too many jobs. It depends on what you want to do. Fire department, and security forces don't seem to be the best, since even in the civilian world, if I recall, all they care about is that you served if you want to pursue those careers afterwards. I'd suggest trying to go into something that involves flying, like radar operations on AWACs or intelligence jobs (those pay a crap ton and open up the doors for FBI and other governmental jobs afterwards). That's what I was going for but unfortunately didn't get chosen for them.
Mind you, you can cross train after roughly 4 years in to another field of you meet the requirements. Avoid maintenance jobs of ou don't like standing out on the flight line rain or shine fixing air craft or equipment. If you feel really daring, try out for SERE which is spec ops training where you'll most likely train to be a para rescue. That stuff is insane.
Whenever you do go, do NOT shave your head, do NOT wear anything with airforce on your clothes or on an item. Bring with you some plane Jane BLACK flip flops, a regular non electric razor, addresses and phone numbers of your family, toothbrush, and as few clothes as possible, you won't be wearing them in basic for long.
As said, practice reporting statements, knowing your ranks and how to recognize their insignias. If you have anyone that has been in recently that can teach you how to do facing movements do it. It may help you from being yelled at if only a little.
You'll most likely be on our face a lot since you WILL get punishe or the screw ups of another person. There really isn't all I can say that will really prepare you for basic. It's something you just have to experience to understand. It's nowhere near as bad as marines or army, but it's stressful nonetheless.