This is done to clear mucus from your child's lungs. You put your child into certain positions and you clap on certain parts of the child's torso. This helps the lungs drain. Remove any rings, watches, or bracelets you are wearing. Position your child sitting and leaning forward about 30 degrees over a pillow. Cup your hand as shown with your thumb next to your index finger. Moving only your wrist, clap your cupped hand firmly against your child's upper back. Clap on the left side of the rib cage first, then the right side. Move back and forth for about three to five minutes. Do these steps with your child in the position that you were instructed to use. Here are some common positions. Apical upper lobes. Position your child sitting and leaning backward at about 30 degrees against a pillow that rests against you. Cup your hand and clap over the area between the collarbone and shoulder blade on both the left and right sides. Anterior upper lobes. Position your child sitting and leaning backward at about 30 degrees on a pillow that rests against you. Cup your hand and clap over the area between the collarbone and the nipples on both the left and right sides. Posterior lower lobes. Position your child lying on their stomach with pillows under their hips and their head lowered 30 degrees. Cup your hand and clap over the left and right of the spine. do not clap on the spine or lower ribs. Middle lobes. Position your child lying on their side with pillows under their hips and their head lowered 30 degrees. Cup your hand and clap over the area below the armpit.