First, set up the desired number (three minimum) of dots by using the plus/minus buttons. When you have the number you want, start the game by making a move. The computer will then make its move.
A move consists of breaking a group of dots into two groups with an unequal number of stones. You divide a group by clicking on the dot to the right of the dividing point.
For example, if you select the third dot of a group of five, you will divide that group into a group of two and a group of three). The computer distinguishes groups by changing colors.
The last player who can make a move, wins. Note you cannot click on a group with one or two members.
The strategy is to leave your opponent with a zero nim sum where the nim values for each heap size are taken from the following table. A discussion of how to add nimbers is here and a discussion of how this table was computed is here. Note that it is conjectured (in Winning Ways for Your Mathematical Plays) that this table eventually settles down to be periodic as is the case with Kayles, this remains unproven despite Achim Flammenkamp having computed this table to 235 dots here:
| Heap Size | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Nimber | 0 | 0 | 1 | 0 | 2 | 1 | 0 | 2 | 1 | 0 | 2 | 1 | 3 | 2 | 1 |