Wow! It looks like the topic has been more intensely discussed than I thought it had.
As others have mentioned, some social aspects are so obvious that they go without saying. This includes issues like stealing and cheating, which most normal people know are no-no's in front of most people, including friends.
But I think that the friendly environment of the gaming table is sometimes enough to slacken some people's social expectations. This means that they may do or don't do things in front of other gaming groups that their previous groups were okay with. Since some groups are also friends out of game, there is a level of comfortability that soothes the players but may shock complete strangers.
For example, when I was still living in the Philippines, it could get really hot when summer came around. So nasty was this heat that one of my players had the habit of either going shirtless or wearing moth-eaten shirts. Not the prettiest sight, but it was kewl since we were all friends around and beyond the table. Since this player knew to never do a thing like that in public or among strangers... barring intoxication or some other mind-affecting effect (drowsiness).
And then there are the people that are in serious need of social training.
Anyhoo, thanks to Joe, Whimiscal, Janx, Ironregime and everyone else who commented, gave suggestions or were so kewl that they provided an example of a conduct guideline.
My game is on thursday afternoon-evening. I don't think that I have to cover the basics that only social deviants are unaware of. With some yoinked material from the above and with the suggestions given, I'll be revising the draft.
