Do not criticise at all; but—if you must—criticise fairly.
Never call attention to the score after the cards have been dealt.
No matter how cleverly the cards are managed, the player who underestimates the attention the state of the score demands will unnecessarily lose many a rubber.
The necessity for keeping the score constantly in mind grows upon all players as their experience in Bridge increases.
Know the requisite number of tricks to be taken, both to win and to save the game.
When you are a game behind, do not hesitate to gamble.