Back in the day, any man who broke “The Code” became a social outcast. Here is a brief list still applicable today as it was back then. 

Don’t judge character by people’s past. Take them for what they are today.
Don’t ask a rancher how many cattle he has; that’s like asking how much money he has in the bank.
Close the gate when you open it.
Say howdy to folks on the trail.
Never order anything weaker than whiskey, unless it’s before noon—in which case add water.
Always fill your, and your guest’s, whiskey glass to the brim.
Do not be ungrateful.
A cowboy always helps someone in need, even a stranger or an enemy.
Maintain humility. A self-centered boaster is not tolerated.
Respect the land and the environment. People come here for the clean air, water, and wide open space. Keep it that way.
Your word is your bond. ‘Round here, a handshake is just as binding as a signed paper contract.