Signalling your partner is only used when you are on defence – it makes no sense to signal dummy or declarer because you know the cards in both hands, signals are only done using your cards any other form of signal is illegal and you can be penalised for it.
How can I show my partner what suit I want led?
There is an important, but often overlooked, defensive area of bridge. Suit preference signals can occur at almost anytime during the play of the hand, and sometimes even on the opening lead. We will be dealing with SP “shift” signals in this lesson(as opposed to discard systems) There are 4 instances in which Suit preference signals can occur:
1.) Partner’s play to the opening lead
2.) In your opening lead
3.) During “mid game” with defensive leads
4.) During declarer’s trump suit play.
Partner’s play to the opening lead
This is where a great deal of confusion often occurs. One of the partners is thinking “suit preference”, while the other one is thinking “continue” or “stop”. Even more confusing is when either situation could be right. As a rule, the first consideration should be “attitude”, conveying to partner that you either want a continuation of the suit, or you don’t.
When you’ve raised partners suit, with or without the Queen in their suit, and partner has led the A from AKa.) Encourage the lead if a shift to any side suit holdings would be unhelpful
b.) Discourage the lead if a shift to a side suit appears to be urgent
c.) A discouraging signal does not indicate a “suit” preference – it merely indicates a “shift” preference.
d.) The opening leader will deem partner’s card played to be an Suit Preference signal when a continuation of the lead suit will be fruitless.
Suit Preference shifts are deemed to be a priority and request
1.) the highest ranking suit, of the remaining suits, by playing an unusually high card in the suit led,
2.) the lowest ranking suit, of the remaining suits, by playing the most discouraging card in the suit led. Remember that a trump suit is excluded as a shift suit.
Whereas a higher suit preference signal can be made anytime (with an unusually high card), a low suit preference is sometimes interpreted and may be easily misunderstood