Set up the charger. In a well-ventilated area, place the included Apple Watch Magnetic Charging Cable or Apple Watch Magnetic Charging Case on a flat surface, plug it into the included power adapter, and then plug the adapter into a power outlet.

Charge Apple Watch. Position the back of Apple Watch on the charger. Magnets on the charger align Apple Watch properly. When using the Apple Watch Magnetic Charging Case, keep the case open. You’ll hear a chime when charging begins (unless Apple Watch is muted) and see a charging symbol on the watch face. The symbol is red when Apple Watch needs power and turns green when Apple Watch is charging.

Check remaining power. On Apple Watch, swipe up on the watch face, then swipe to the Battery glance.

You can also add the battery indicator to many of the watch faces, including Modular, Color, Utility, Simple, Chronograph, and Mickey Mouse. With the watch face showing, firmly press the display, tap Customize, then swipe to the left until you can choose individual feature locations. Tap a location, turn the Digital Crown to choose Battery, then press the Digital Crown to exit.

Use Power Reserve to stretch available power. You can put Apple Watch in Power Reserve mode to save power when the battery is low. Apple Watch still displays the time, but you can’t use other apps. Swipe up on the watch face, swipe to the Battery glance, then tap Power Reserve. You can also press the side button until you see the Power Reserve slider, then drag it to the right.

Return to normal power mode. Restart Apple Watch—press and hold the side button until you see the Apple logo. The battery must have at least 10 percent charge for Apple Watch to restart.

Check time since last charge. Open the Apple Watch app on iPhone, tap My Watch, then go to General > Usage.