Using your GMS2110 watch is a breeze. Simply wear it on your wrist like any other watch. The shock-resistant feature means you don't have to be overly careful if it accidentally bumps into something. However, try to avoid dropping it from a great height. For battery replacement, when the watch starts to show signs of low power after about 3 years, take it to a professional watch repairer to replace the CR1025 battery. To keep it looking great, clean the watch regularly with a soft, dry cloth. Since it has 200-meter water resistance, you can wear it while swimming or in light water activities, but avoid exposing it to hot water or steam for a long time. Also, keep it away from strong magnetic fields as they may affect its performance.