Using this Tyro kids' bike helmet is a breeze. First, put the helmet on your child's head. Then, use the Fidlock magnetic buckle to quickly and easily secure the chin strap under the chin. Make sure it's snug but not too tight. Next, adjust the rear dial until the helmet fits your child's head properly. When your child is riding, always make sure the helmet is worn correctly. As for maintenance, you can clean the helmet with a mild soap and water. Don't use harsh chemicals as they may damage the helmet. Check the helmet regularly for any signs of damage, like cracks or loose parts. If you notice any, it's time to get a new one.