Break off about 18 inches of floss and wind it around the middle fingers of each hand. Hold the floss tightly between your thumbs and forefingers. Guide the floss between your teeth using a gentle back and forth motion. When the floss reaches the gum line, curve it into a "C" shape against one tooth and gently slide it in an up and down motion on one side of the tooth. Bring the floss back toward the contact point between the teeth and move the floss to the other tooth and repeat the "C" shape motion.