All bids and plays should be made at an even tempo without variation in manner, demeanour or tone of voice.
It is a breach of the proprieties to take advantage of partner’s inadvertent mannerism or change of tempo.
Don’t make any adverse remark about another player’s bidding or play (even partner). Breaches will be penalised at least 3 IMPs or 10% of the available matchpoints for the deal.
Do not publicly or privately report on any player’s irregularities to any person other than the director. (To accuse a player of cheating is itself a serious breach of etiquette, except privately to the director).
If you gain unauthorised information about a hand (e.g. from overhearing remarks at another table or seeing another player’s cards or partner’s mannerism) call the director immediately, in particular, if partner by her/his hesitation has possibly conveyed information, call the director forthwith.