Using this watch is a breeze. First, pair it with your smartphone via Bluetooth®. Just follow the instructions on the app to sync the time and access additional features. As for water resistance, it can handle swimming and snorkeling up to 200 meters, but avoid deep - sea diving. When it comes to maintenance, keep it away from extreme temperatures and strong magnetic fields. Clean it regularly with a soft, dry cloth. If the watch is exposed to saltwater, rinse it with fresh water. Also, make sure to replace the battery as needed to keep it running smoothly.