Use your left and right arrow keys to move the blob you are controlling and press spacebar to fire it. Your up and down arrow keys rotate the board allowing you to position the blobs all around the grid.
Arrange the blobs on the board in their color groups. If you match the pattern and color shown on the left of the screen the group will be removed and set off a chain reaction.
All other blobs of the same color which are touching the pattern will also be removed scoring bonus points.