i had a sea bag, much easier to carry. pack another set of civilian clothing. i already had insoles in my boots and would run in the them to get them in good form to my feet. i brought footpowder and moleskin, because it will be maybe two weeks before you can go to the PS to get supplies. brought my two sets of boots and if i were you i would consider purchasing PT boots. much more comfortable on humps and long runs. you dont need to by shower shoes because you will by them there, its party of many things you will buy. i would also buy a good permanant marker that will not come out on clothes. 1 inch tape. not the thicker athletic tape. bring stamps if you want to write to anybody. cell phone if you want to. i would not bring anything of great importnance because when you get your Sgt Instructors and Plt Sgt and Plt Cdr. you will end up dropping all your trash on the deck anyways. so you dont want to lose something valuable. dont stress too much. you ll learn quickly and if you dont then you wont like it and more than likely DOR or get kicked out. if i were you all take the three to five days prior to OCS and relax, not PT, just relax, your body will need it.