Using these Izipizi sunglasses is easy. Just open the arms and gently place them on your child's face. Make sure the lenses cover the eyes properly for full UV protection. When adjusting the silicone strap, find a comfortable fit so the glasses stay in place. As for care, use a soft, clean cloth to wipe the lenses. Avoid using rough materials that could scratch them. Keep the sunglasses in a case when not in use to prevent damage. Also, remember to check the fit regularly as your child grows.