How to play Contract bridge well once you know the rules: the decisions that matter, and the habits that win.
The standard way to value a hand is high-card points: ace 4, king 3, queen 2, jack 1. There are 40 in the deck, and an average hand has 10. With 12 or more you should usually open the bidding; with fewer, pass and let the auction come to you.
Add a little for shape. A long suit is worth tricks that points do not show, and a hand of 11 points with a six-card suit plays better than a flat 12.
Eight cards in one suit between you and your partner is a fit, and a fit in hearts or spades is the most valuable thing an auction can find. A game in a major needs ten tricks, four hearts or four spades; a game in no-trump needs nine, three no-trump; a game in a minor needs eleven.
Twenty-five high-card points between the partnership is roughly what a game needs, and 33 or more is the zone for a small slam. Use your bids to tell your partner how many points and which suits you hold, not only to reach a contract.
When dummy goes down, stop. Count your sure winners in a no-trump contract, or your losers in a suit contract, and decide where the missing tricks will come from before you play a card from dummy.
Most contracts are made by setting up a long suit, taking finesses, or trumping losers in the hand with fewer trumps. Draw trumps early when your side suits are solid; delay it when you need dummy's trumps to ruff.
Against no-trump, lead your longest suit — the fourth-best card from the top — to set up tricks for later. Against a suit contract, a lead from the top of a sequence like king-queen-jack is safe and strong, and a singleton can let you ruff a later trick.
Leading away from a king or an unsupported ace against a suit contract gives declarer tricks. When nothing looks good, the suit your partner bid is usually right.
Defenders can see only half of their side's cards, so the cards you play are signals. A high card on partner's lead usually says you like the suit; a low one says switch. Agreeing on even that much makes defence far easier.
Count the cards declarer shows. By the middle of the hand you can often work out their exact holding in a suit, and from there which of your cards will win.