"don't touch my junk" well said and intended. Divers learn set up in OW, if they are occasional resort divers, they should relearn, "look but don't touch" might be added. If they are having a problem, suggest, if they are doing it differently, ask, if they are doing it wrong, advise. But please let them set it up themselves, that's part of the dive and learning curve. Ok they may need a Scuba Review too. Of course, as DM, a careful and watchful eye may prevent a few problems, at least a quick BWRAF before entry, Watching the divers set up on top, may indicate who needs to be more closely watched down below. And speaking of liability, WOW, doing anything outside the limits of training and standards, WILL increase both risk and liability.