Just bring some civilian clothes you don't really care to much about and a pair of glasses that you don't really need (if you wear them). Everything else will be confiscated except for 1 book and the bible. Everything else will be provided or bought at the first trip to the BX ... or PX whatever you Army guys call it.
At least that was the way it was when i did USAF boot camp in 2001. Good luck and thank you for serving.