Using your Casio Edifice Slim Series watch is easy. Just look at the three hands on the dial to tell the time, and check the date display if you need to know the date. When you're near water, remember it's 100-meter water resistant, but it's still not recommended for deep - sea diving. For battery replacement, after about 3 years, take it to a professional watch repair shop to replace the SR916SW battery. To keep your watch looking great, clean it regularly with a soft, dry cloth. Avoid scratching the sapphire crystal by keeping it away from rough surfaces. Also, store it in a cool, dry place when not in use.