Call The Director
I write this in the hope of clearing up some murky situations. First let me say any time there is or may have been an infraction please call the director before doing anything else. I will try to address a few of the more contentious issues.

Law 45 deals with when a card is played. There two things about this that sometimes confuses people. First the rules for declarer and defenders are slightly different and have some latitude for a director's interpretation. Each player except dummy plays a card by detaching from their hand and placing it on the table face up in front of themselves. If a defender holds their card so that it is possible for their partner to see it, it must be played. A declarer must play a card if it is held face up touching or nearly touching the table. As you can see, there is therefore some judgment the director must use when deciding whether the card was played or not. To further confuse the issue, law 45 C. 4. b. (we are in the fine print here) " Until his partner has played a card, a player may change an unintended play if he does so without pause for thought. This may be done even if the next opponent has played. If the rules allow a change even after an opponent has played, it certainly becomes a decision by the director if it could be changed without pause for thought. Suffice it to say it is helpful to make a positive decision to play a card before detaching anything from your hand. Also the rules are there to rectify irregularities and re-establish equity, not to penalize one side or the other.

Laws 24 to 39 deal with the auction. Each time there is an irregularity, call the director. Some people think if you correct an insufficient bid with a sufficient bid in the same suit there is no further penalty. This is true in the vast majority of situations, but there is no requirement to make a bid sufficient and in fact LHO has a right to accept the insufficient bid. If either the original bid or the corrected bid would be artificial in your methods just making the bid sufficient does not finish the situation. The permutations of happenings are too many to discuss here, just let me say call the director. Further discussion or attempts to make a ruling by the players might compromise your rights.

The most common problem I am called to the table for is opening leads out of turn. To solve this problem lead face down and make sure it is your turn to lead.

Law 42 deals with dummy's rights. Law 42 B. 3. states " Dummy may draw attention to an irregularity, but only after the play is concluded." However dummy is allowed to try and prevent an irregularity by declarer. IE. The dummy may ask declarer (not a defender) if he has a card in a suit to which he did not follow.

I think also that it is important to remember that we play Bridge for enjoyment. Directors do their best to interpret the rules fairly. However, errors do occur. I recall seeing a pitcher lose a no hitter on an error by an umpire. He apologized later but that no-hitter does not exist. We have all seen Professional umpires and referees make errors. It should not astound us that our directors might make an error from time to time. However as head of directors I have never seen or encountered a director who does not do their best to fairly interpret the rules. I just have one request of players.

When irregularities occur call the director