Using these sunglasses is super easy. Just put them on your child's face, and the flexible arms with spring hinges will adjust to fit their face comfortably. When it comes to maintenance, keep them in the included storage bag when not in use to prevent scratches. Clean the lenses with a soft, clean cloth. Avoid exposing them to extreme temperatures or sharp objects. And remember, these sunglasses are for children aged 5 - 10, so make sure your child is within this age range for the best fit and protection.