It's easy, really!
Don't be a dick. Don't intentionally do anything to make anyone feel bad while you're here. Don't insult people or belittle them, and CERTAINLY don't use slurs.
Don't advertise your stuff. I mean that kinda falls under 1. as well because it IS a huge dick move.
Speaking of the word dick: Do not get explicitly NSFW in chat. I'm not gonna cry if you make a crude joke usually but y'know, don't get horny here.
And thats pretty much it!! Most contingencies fall under one of these. :]