As the swinging snakes regurgitate the cute little guinea pigs you must click the snakes, which will release the pigs. As gravity finds there resting place they will blow a bubble of gum that will pop and splatter on the unsuspecting victims, although by the 54th level they may no longer be called unsuspecting.
Mouse Click: Click the snakes at specific times to release the Guinea pigs. Then wait for the guinea pigs to blow a bubble and splatter on the animals. Sometimes you will be required to click other leavers as well.