The Initial Draw
The strategy you choose should be determined by your initial hand. To determine a winning strategy at mahjongg, look at the number of tiles you need to get for a winning hand. If you need only four, then you have a strong opening, and should play to win. If you need six or more, then your odds of winning are not good. In this case you should choose a defensive strategy and try for a draw. If you need five tiles, then you should watch what you draw in the next couple of turns. Good draws early on can allow you to go for victory, but a five tile deficit and bad early draws mean you should play for the draw in that round.
Greater Knitted Tiles and Honors
In addition to such general guidelines, there are special strategies to adopt depending on circumstances. If you have a hand with all single tiles and no pairs or melds, then you should try for single honors. Singles of all seven honor tiles make for the Greater Knitted Tiles and Honors combination, which scores relatively well. Other combinations of single honors score well, too.
Three-Suited Terminal Chows
A sequence of three tiles of the same suit is called a chow. If you have two Terminal Chows in two different suits and a pair of fives in a third suit, then you may be tempted to try for a Pure Straight, an Outside Hand, or a Mixed Triple Chow. However, a winning strategy that even good players might miss in these circumstances is to discard some of these opportunities and try for Three-Suited Terminal Chows, which is two Terminal Chows of the same suit and one Terminal Chow from a different suit, according to mahjongg experts at the Takeshobo Mahjong Museum.
Mixed Shifted Chows
As an all-around general purpose strategy, you should always be ready to try for Mixed Shifted Chows, three sets with each set made from one suit. They are the "workhorse" sets of mahjongg, according to Tom Sloper, author of Weekly Mahjong. Some mahjongg champions swear by them.