Declarer has the advantage of being able to see dummy's cards as well as her own, planning the play as one unit. A defender can do none of this. All one has is inferences from the bidding and a view of the dummy after the opening lead. The defense also has the advantage of making the opening lead, which may or may not be a positive message. Intelligent defense needs a large amount of cooperation between partners. This can only work well if both partners have an agreed system of legal signaling.
Declarer watches your signals also, and he understands them so do not give a count signal if it is going to be of real value to declarer. I usually do not give a lot of count signals in notrump contract since we can use the opening lead attitude signal and the suit preference signal. Remember, most folks give too damn many signals, so...be kind to yourself and partner and play with your brain and not your signals.
You must always look at the opponents card for leads and discards, and if there is something you do not understand, ask them before playing to explain them to you and ask them again when the card is played as to its meaning. This will delay the hand and they will think you are a pain in the butt, but they will also respect you for asking. Don't let someone else’s signal be a plus for them simply because you are too lazy or too frightened to ask what the hell it means.
We will be using all three types, but first, some general rules about signals...
We will use attitude signals and count signals in both defending trump and notrump contracts..and to a more limited extent we will also use Lavinthal suit preference, so let’s take each category of signal and find out what I am talking about.
When you give attitude to your partner, what you are saying is simply this: Partner from my hand and what I see on the board...my attitude to the suit you just lead is ????? Signals in both types of contracts also. If you now play a big card ...you are saying "I love this suit partner..lead it again!" If you play a small card ...you are saying: " this suit stinks, partner, try another one."
If you can see the two, three, four, seven of a suit..then the eight is most likely a small card. On the other hand, if you can not see these small cards in your hand, dummy or the card played by declarer, the eight would be a large card.
The attitude signal is your primary responsibility. The signal must be given by you even if it means upsetting any count signal. This is especially true in notrump contracts. Whenever partner leads a suit against notrump, you must tell her immediately whether or not this suit has a chance of being established. If you remember, the suit is viable if you and partner have seven of them or more, and if you and partner have potentially enough of the honors to set the suit up…large card on opening lead says yes it is viable, while small card on opening lead says: no, partner this suit is not viable try to find another one.
Now..the second kind of signal should always be shown on every lead. As long as it does not upset the attitude signal, you play high/low for an even number in the suit and you play low/high for an odd number in the suit. Most of you are used to this kind of signal for two card suits…you call the leading of high then low an echo, but it is also used to show four card and six card and eight card suits..all even numbers. Low then high are played to show one card suits, three card suits, five card suits and seven card suits.
You must try to give this signal every time in all suits but trump.
A special procedure is used to give count in the trump suit. The order of play is reversed. You suggest an odd number of trumps (nearly always three) by playing your middle trump, then your lowest. To show an even number, play your lowest trump first.
There are several reasons for reversing the signaling method. Firstly, with only two trumps, your highest one may be too valuable to waste (Qx, Jx, 10x, or even a 9x may promote a trump winner for your partner). Secondly, a high-low, showing three trumps, will suggest to partner that you may:
be able to trump a suit (in which he knows or suspects a shortage) or b) it is imperative that you get the lead so that you can lead a third round of trumps -- taking two for one -- in order to thwart a cross-ruff game. Thirdly, a count in the trump suit may help partner to work out declarer's distribution.
We will use Lavinthal in three ways: one way in notrump contacts, and two ways in trump contracts.
In notrump, you will often find yourself running out of cards when either partner or declarer is leading a long suit. When this happens...the very first time you must discard another suit in either situation. You must learn to give a Lavinthal suit preference signal and here is how it works:
Example:
If partner is running hearts, you discard a high spade. Since it is a spade you discard...you do not want a spade led and since the spade you discarded was high..you must want diamonds led, since a low spade would have asked for clubs.
One of the nice things about Lavinthal is that you will be able to pick and choose your signal from two suits you do not want led. This will always mean you will have the easy card to signal with. There will never be a problem in finding a card to signal with.
Say partner is running spades. You have run out of spades and must discard. You hold the ace, king, queen of diamonds and want a diamond lead. You can discard a low club asking for a diamond, or discard a high heart asking for a diamond. You discard low for lower suit you want led or high if you want higher suit led. The suit preference signal works because you can eliminate one of the four suits automatically -- the one you just ran out of. This automatic elimination of suits also allows us to use Lavinthal in trump situations because we can automatically dismiss the trump suit.
So we can use Lavinthal in two situations in a trump contract. First, we must use Lavinthal..whenever partner is about to trump your lead and you know that partner is about to trump and partner knows that you know that he is about to trump. In that situation, you play a high card for a higher suit return and a low card for a lower suit return. If trump is spades and you are leading hearts, and you know that partner will ruff the heart lead for a win, you lead a high heart asking him to come back in diamonds. And you lead a low heart asking him to come back in clubs.
The last use for Lavinthal is much less known and a little more complex to understand. Again in a trump suit, when partner is leading a suit out...and you can tell the moment that dummy comes down..that partner will never want to lead that suit again, and partner can tell that you can tell that he will never want to lead that suit again……
In both those examples, it is obvious to both of you he will never want to lead that suit again. In that case and only in that case...your play to the ace is suit preference.
This signal works because attitude is no longer of any relevance . A high card for attitude means: I like this suit, partner lead it again. A high card as a suit preference signal means switch to the higher of the two suits left.
On your convention card, you can write in lower left on signals “ standard with limited use of Lavinthal”
There are many ways to give count and attitude. The way I have just taught you is the standard way, but you are going to see things like this on some folks cards: Upside Down signals, Odd/Even signals, Journalist leads, and Rusinow leads. These will all point to non standard ways of making leads and giving signals.