Using this Kamen Rider OOO watch is super easy. You can simply swap the colored glass medals according to your preference. To change a medal, just gently open the watch's designated slot and insert the new colored glass. When it comes to maintenance, keep the watch away from water as much as possible. If it gets dirty, you can use a soft, dry cloth to wipe it. And remember, don't drop the watch or expose it to extreme temperatures. Enjoy wearing this unique watch and show off your swappable medals!