To use this helmet, first choose the right size according to your child's head circumference. Make sure the helmet sits level on your child's head, covering the forehead. Adjust the straps so they fit snugly but not too tight. When your child is riding, always check that the helmet is in place. As for maintenance, clean it regularly with a mild soap and water. Don't use harsh chemicals as they may damage the helmet. Store it in a cool, dry place when not in use. If the helmet is ever involved in an accident, replace it immediately for safety reasons.