ACBL Ten Commandments for Bridge Players

Do not criticize or express disapproval of an opponent’s play or bid
Do not comment to the effect that it was the opponent’s error that required you to succeed.
Do not offer unsolicited advice.
Do not discuss previous hands in front of new opponents.
Do not engage in lengthy post-mortems between hands.
Do not engage in loud arguments with partners and embarrass opponents.
Do NOT engage in cross-table conservation once the bidding has commenced.
Do not slam your cards on the table.
Do not have a card ready to play before the previous player has played.
Do NOT remain at the table after the change has been called or fail to pass the boards to the next table.
(Very ‘weathered’ document from AWC: c1980 ) ‘Excerpt from the Nov. Bulletin’.