1:Never drag, punch, or pull someone into a mosh pit if they don't want to go; if they wanted in, they'd be in by now.
2:No cheap shots.
3:If someone gets injured in the pit, you get them the fuck outta there and to a medic. It doesn't matter what it takes or what you lose, these people are your concert-going extended family; you stand by them.
4:Never hit someone harder than they can hit you- sounds stupid, but do you really want to be That Guy?
5:Do NOT curbstomp someone if they trip.
6:Generally speaking, don't be a total fucking douchebag.