If you can; set up a logistics line that can get you stuff you figure out you need, and are allowed to have, as you move through PS.
Mole Skin, Cool towel, spray bottle/fan, shot blocks, electrolyte tabs for water, under wear (a DD thing I think), also sports bra (same, same), a protein bar or two if a meal is missed, a calf sleeve, Etc. All stuff we sent to DD during plebe summer. From our vantage point sending "care packages" things seemed to loosen up in terms of what Plebes were allowed to have as they settled into week 3-4-5 of PS, (DD said it what was allowed varied from platoon to platoon).
If you are a guy who is more "on your own" than other Plebes DON'T HESITATE (NOT EVEN FOR AN INSTANT) to ask a fellow plebe if you need something running socks, mole skin, Calf Sleeve as PS progresses. There are Parents at home that would like nothing better than to pick up and mail something that one of their plebe's squad mates needs-----you'll probably snag some cookies too.
I'm with Zeus, I think you asked a reasonable question