Never talk back to the NCOs.
Keep a straight face at all times when dealing with people who outrank you.
Work on your physical fitness beforehand, if possible. It will make boot camp much easier for you.
Particularly in firing ranges, follow the instructions TO THE LETTER. They are there to make sure there aren't any accidents.
Agree early on with the guys in your room what your lockers will look like. They have to look exactly the same or else you'll do it again during inspections.
Treat your equipment with respect, particularly your gun. Because if you don't, you'll just have to do it all over again.
Maintain good out-of-service relationships. Even though my relationship went belly up six months after my service, I would have gone bonkers if I hadn't spent time on weekend leaves with my girlfriend.
Learn the loopholes and use them to your advantage.
Build up a tolerance for boredom. You'll always have to wait long times before you rush, or you'll have to rush to get to wait for a long time.
If possible, maintain a stash of private rations in case of bivouac or being confined to barracks: caffeine tablets (don't OD on 'em), cigarettes, chocolate, canned tuna etc. If the bivouac food is inedible, at least you'll have something to give you a boost.
If you smoke, use that to your advantage. Smokers sometimes get breaks.
If food in bivouac is inedible, use your private stash. But remember to keep yourself in liquids: you can survive a while without the crap they call food, but you'll definitely want all the tea/coffee you can get.
Volunteer. Just do it. It's a gamble, but there's a chance you'll get something nice.
Learn the local slang.
Learn to take a joke, there's bound to be a prankster or two in every company.
If not currently doing anything, find a place where the NCOs are least likely to see you right away; this way you can avoid often shitty extra service.
