Using your Daniel Wellington Petite Moonphase DW00100771 is a breeze. Simply put it on like any other watch and adjust the mesh strap to fit your wrist comfortably. To set the time, gently pull out the crown and turn it until you reach the correct time. Then, push the crown back in. This watch is water-resistant up to 30 meters, which means it can handle splashes and short periods in the water, but don't wear it for swimming or diving. When it comes to maintenance, keep it clean by wiping it with a soft, dry cloth regularly. Avoid exposing it to harsh chemicals or extreme temperatures. If you notice the watch isn't keeping accurate time, it might be time to change the battery. You can take it to a professional watch repair shop for battery replacement.