First, get your contract set up with what you want. Don't go in under an open contract.  Second, remember that your job isn't guaranteed, only the job grouping. That means they can place you specifically in another job. Next, you want to remind yourself that this is YOUR CHOICE and you WANTED to be in there. Some people can get bitter and get mad at other Marines, the Marine Corps itself, or the Drill Instructors, but nobody forced you to enlist. It was your choice, remember that. Stand by it, work hard to accomplish your goals. Next, be your own medical advocate...no one else will be. I was hurt and had to still do work because none of the docs cared enough to pull me to the side. I really messed up my feet from it. Always keep a copy of your medical paperwork. It may become cumbersome but you will be glad you kept it.  Next, you're human, you'll make mistakes. Never take it personally when someone corrects you. If they directly insult you, don't take that personally, either.  Finally, and this is big, keep your ducks in a row and make sure you speak tactfully...then you can pretty much talk shit to anyone as long as you do it properly. For example, when you want to say, "It's in the fucking black and white" when referring to a rule or regulation, you can say, "To my understanding, it is X".