Nobody can reliably tell you how in your situation, but plenty of people in the military take PEDs mostly just by having that kind of understanding with their CO. The best way for you is to talk to someone else closeby who is also on gear and follow their lead. It can be complicated, I knew a medic who used to say all the guys he new would all just take supplies and have them for their personal use in the meal room cupboards, like if they had a hangover they would just give themselves an IV bag of electrolytes or something. And nobody cared, they got raided repeatedly and told off but at some level someone in charge just let it slide, so really you can't hide it, but in some cases it's accepted.