Tip 1 -   Contract 4 ª by South           (Degree of difficulty = 5)

West leads the Jack of diamonds. How should South plan his play?

With a fair distribution of the lacking trumps, South has only 3 losers. The danger could come from the lead suit if it was made from a doubleton: since you have to give the hand to opponents twice when you draw the trumps, opps could go on playing diamonds till West ruffs and sets the contract.
Is there anything South could do? This is one of the cases in which, even if you have a number of tricks sufficient to make the contract, you do not have to draw trumps but you need to discard a possible loser before.
Have a look at the hearts. Not only can you make 2 tricks in the suit, but you have at dummy an extra trick which you can discard a diamond on. Doing so, you'll not take risks to be ruffed on the third round diamonds.

Tip 2 - Contract 4 ª by South (Degree of difficulty = 2)

West leads the 4 of hearts. How should South plan his play?

Planning: You could ruff 2 clubs at dummy, giving only one club and the Ace of diamonds after having drawn 2 rounds trumps. Instead if you play at once club to begin ruffing in the suit, you could bitterly regret it! In fact if the leading attack was coming from a singleton, the partner of the leading player would take at club and he would give a ruff playing  a high heart, calling for a return diamonds (Lavinthal). He would take again and woul give another ruff to his partner and a sure contract, with a possible overtrick, could  be set 1.

Tip 3 -   Contract 3 NT by South           (Degree of difficulty = 10)

West leads the 3 of spades. How should South plan his play? The game isn't sure, but you must try to protect yourself in some way!

After ducking only one time the initial lead accordingly to the Low of the 7, you take the return spades with the Ace.
Since to make your contract, you have to estabilish  the club suit, but you have to give a trick in the suit to opps.
The danger is that west take the trick and if he led from a 5 cards suits, he could cash now 3 spades and the contract coul be set. Look at the complete diagram: can you see a way not to give the trick to west while estabilishing the clubs?
If you tell me that you would play just a major Honor, and then play a little club to force East to take and not west, I answer you that East is a good player and when you play your club Honour, he would unblock discarding the queen of clubs to let his partner take a trick in the suit.

What do you have to do then? You should take into place that technical manouvre called as "Kiss to the Queen" that consists of letting the queen take the trick (when estabilishing a long suit where you have to give the hand tyo opps) if she is in the hand of a not dangerous player!
So you should go to dummy in a side suit and play little club towards your great honours and to cover every card East plays, but the Queen which you would let taking the trick. Doing so, doing the Honours to the Queen, not only have you given a white coup, but you have also evoided East (the side dangerous) taking the trick.
Yes, you have right…… If it is west to have tre cards with the queen, there is nothing you may do…. The contract would be set….. But you would have done everything you could do to maintain the contract!

Tip 4 - Contract 4 © by South             (Degree of difficulty = 3)

West leads the Ace, the King and the Knave of diamonds. How should South plan his play?

South should ruff the third round of diamonds and play the Ace, King and another heart, giving the opps their last trump at once. East wins and retourns a spade. South goes up with the Ace, cashes the Ace § and continues clubs discarding his two loser spades. He makes 5 hearts, 1 spade and four clubs.

Tip 5 - Contract 4 © by South (Degree of difficulty = 3)
West leads the 2 of spades. East wins with the Ace and comes back a spade for West's King, who now switches a club. You try the finesse, but East takes with the king ad switches a diamond. How should South plan his play?

The diamond finesse will presumably have to be taken eventually, but there is no need to risk at this point (West could have the Queen singleton, even if it is difficult to believe). But that is not the problem….. Taken with the Ace of diamonds now you have to draw trumps first. You have to use a precaution play in order to be able to capture a knave fourth: South has to start playing the King of trump and, when East doesn't follow in the suit, he plays also the Queen and then a little heart towards dummy finessing the Knave.

Tip 6 -   Contract 3 NT by South           (Degree of difficulty = 6)

West leads the King of diamonds. How should South plan his play?

South should refuse to go up the K ¨ (Bath Coup) forcing west to switch or to sacrifice a trik in the suit.
Suppose he switches to a club. East makes his King and returns a diamond, but now South has 9 tricks.
If West switches the Queen of hearts, South plays the Ace © and then Ace § and a little § giving the King to opps and he has still 9 tricks.
If West continues diamonds at trick two, the declarer will make now an overtrick.

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