2048 numbers
Merge equal numbers until you reach 2048. Every move has to be thought through.
The rule that decides everything
The board has 16 squares. A new tile appears in a random one and you move everything at once. Two equal numbers become double.
Corners are more than a preference
Playing into the same corner keeps the high numbers grouped and the rest of the board open. It is the method most used by players who get far.
Note
There is no guaranteed strategy. There is only practice.