Every so often, you will have an inspection. You'll be given about a day or two in advance. Some inspections are more detailed that the others, and as OCS progresses, you'll be inspected by higher ranking instructors. Off the top of my head, there were four inspections:
Instructor inspection- can be any instructor. These are chaotic but don't take that long.
Platoon Sergeant Inspection- by your PS. This can take a while.
Platoon Commander- by your PC. This can take a while.
Battalion Inspection- This is by the OCS Commanding Officer. This is the last one, and it'll involve only the people who are graduating. When I went, Charlie Company (the other company) all lined up in formation on the parade deck and got inspected one by one. They were there forever while we did drill. When it was our turn, we were in our squad bays and it went platoon by platoon, but I believe we still stood there the whole time. I had a broken foot by this point and got to sit on my camp stool, but others had to stand the whole time. One person in my platoon rolled their sleeves way too tight and I think locked their knees. During the inspection, the stumbled awkwardly into the aisle, white as a ghost. Another candidate and I caught them before they fell and I got to render preliminary first aid to her. (Lay them on their back, prop their legs up...I used rolled towels from the locker...and loosen their clothes).
The first three inspections, you will get graded, but don't stress, this counts for so little of your grade. Worry more about a good appearance and having your gear squared away. I will list the things that get inspected, but these don't get inspected all the time.
Yourself- your grooming, your uniform. You'll be asked (screamed at) basic knowledge.
Your rifle- You will have to do some functions and commands.
Your wall locker- arrange it how it is in the candidate guide. Your foot locker doesn't get inspected.
Your "junk on the bunk"- this is your gear, properly laid out, and labeled. Use the candidate guide. Make fresh labels. Our gear had gotten soaked the day before and I just put new ones over top. One of the labels betrayed me and started to peel off, revealing a dirty gross label underneath.
"WHAT..." *rip*. "IS THIS?" One of the male instructors saw the label and yelled at me about it. "THIS IS LAZINESS!" It was such a ridiculous situation that I just yelled back loudly, then laughed about it later.