Using your Baby - G MSG400G - 1A1 watch is easy. To set the time, you can use the buttons on the side. For the world - time function, just find the city you want and select it. When using the stopwatch, press the start button to begin timing and the split button to record split times. The countdown timer can be set by inputting the desired time. The alarms can be set to wake you up or remind you of important events. When it comes to the LED light, it turns on automatically in the dark or you can press the dedicated button. As for the hand - shift feature, it activates when you need to see the digital display clearly. Some things to keep in mind: don't expose the watch to extreme temperatures or high humidity for a long time. If it gets wet, dry it with a soft cloth. To maintain it, clean the watch regularly with a mild soap and water solution and then dry it thoroughly. This will keep your watch looking and working great for a long time.