To use this Kamen Rider Zero One chronograph watch, first, set the time by pulling out the crown and turning it. The chronograph function can be started, stopped, and reset using the buttons on the side. When wearing it, make sure the strap fits comfortably. Keep it away from water as much as possible to prevent damage. If it gets dirty, use a soft, dry cloth to gently wipe it clean. Store it in a cool, dry place when not in use.