Whenever three or more bubbles of the same color are shot together they disappear/vanish. So try to place the bubbles of the same color together so that more bubbles explode and vanish and you get more points. For placing the bubbles you need to point the mouse in the direction you want to place them.

The more bubbles you shoot at one go the more points you earn. Several such fouls lead to add a new line of bubbles at the top. The number of fouls allowed before the bubbles is shown by the number of silver balls left in the leftmost bottom corner. The game would not get over until the bubble doesn’t touch the lower frame so just keep on shooting the bubbles of the same color and get the best scores table saved to the disk.