Your first objective is to find out if your side posseses the strength and distribution to make a game contract. You're aiming at the rubber bonus of 500 or 700, which you can only get by bidding and making game twice.

The game contracts, in order of preference are:

1. 4 Hearts or 4 Spades
2. 3NT
3. 5 Clubs or 5 Diamonds
4. 4NT
5. 5 Hearts or 5 Spades
6. 5NT

It would seem that 3NT would rank first because it only requires nine tricks, but not so. If your side holds eight cards in hearts or spades, you're more likely to make ten tricks playing in the suit than you are to make nine tricks in notrump. Hearts and spades are referred to as the major suits for that reason. 3NT is the second priority, because it only requires nine tricks to make.

If your side holds a little extra strength, and you can't play in a major suit or notrump, then and only then do you consider 5 Clubs or 5 Diamonds, because those contracts require you to make eleven tricks, not nine or ten.

You want to avoid if at all possible playing in 4NT, five of a major or 5NT, because you don't get any bonus for going that high, only increased risk. If you play 3NT or four of a major and make extra tricks, you get exactly the same score as if you bid higher.

The Trump Suit

When considering a game contract, endeavor to play in a suit where the partnership holds at least eight cards, more if available. The most important factor is number. The strength within a suit is secondary in priority to length by a wide margin.