Do not bid or play with special emphasis, speed or reluctance, or in such a way as to deceive your opponents or to convey improper information to your partner.
Do not draw any inference from the fact that partner has hesitated or bid with unusual emphasis or speed. Always make you bid strictly on the basis of the cards that you see. Should your partner convey improper information by word or hesitation, you must lean over backwards to avoid being influenced.
Do not request a review of the auction, or a trick, in order to alert partner to something you fear he may not have noted. Also, do not seek an explanation of a bid, whose meaning you know but you suspect that partner does not.
Do not use any bid having a special meaning to you and your partner unless it has been noted on your systems card. Even so, you are still obliged to alert the bid when relevant.
Do not detach a card from your hand before it is your turn to play, and before you have decided which card you will play.
During the auction, or play, do not call your partner's attention to an item on your opponents' systems card that you think he may not have noticed. It is your partner's responsibility to find out for himself what conventions your opponents are using. Also, do not look at your own systems card if your partner makes a conventional bid, whose meaning you have forgotten.
Avoid any indication of approval or disapproval of partner's bid or play.
Always maintain a courteous manner towards your partner and your opponents
If you are defending and you want a review of the bidding:
If on lead, ask about the entire auction.
If not on lead, the same as a) but wait until partner has made his lead, face down.
Always call the director if a problem arises.
When checking the scores on the Bridgemate do so in silence, making no comments. Also, do not waste time going through all the other scores that appear on the screen.