To use these sunglasses, simply place them on your toddler girl's face. The removable neoprene strap can be attached for extra security when needed. Make sure the sunglasses fit properly and are comfortable for your child. When not in use, store them in a safe place to avoid scratches. Clean the lenses with a soft, dry cloth. Avoid using harsh chemicals or abrasive materials. Check the strap regularly for any signs of wear and tear. These sunglasses are designed for toddlers sized 2T to 5T, so ensure the size is appropriate for your child.