The most effective technique, that won't damage the enamel or injure the gums, is to brush in a circular motion, going over all of the sides of the teeth. It is recommended to brush the same area several times, and brush the upper teeth separately from the lower teeth. You should also tilt the brush at a 45° angle away from the gums.

Always brush from the gum to the tip of the teeth (pink to white) to avoid the bristles hitting the fragile edge of the gums. Be sure to avoid up and down movements as this damages the gums and pushes the bacteria into the space between the tooth and the gum.