Each hand won is scored as a mark. The partner team who score seven marks first wins the game. This is done by playing a domino with the high end equal to one end of a held double when the player cannot follow suit in a trick. Trumps are like a suit in cards. When a trump is led, each player must play a trump if he has one.
High trump wins the trick.
If a non-trump domino is led, and a player cannot follow suit, he may play a trump if he has one. The highest trump played always wins any trick. A player may play any domino if he cannot follow suit. In any case, whoever wins a trick leads the next domino. The object is to bid wisely, make your bid, or help your partner make his bid.