Using the Fenix HM70R headlamp is a breeze. First, insert the 21700 Li - ion battery. If you want to use a 18650 battery, put it in the ALF - 18 battery holder. To turn on the headlamp, press the large thumb - sized switch. You can cycle through different light modes, including white, neutral white, red, and red flash. When it's time to charge, just plug the USB Type - C cable into the hidden charging port. It supports 2A charging current, so it won't take too long. As for maintenance, keep the headlamp clean. Wipe it with a soft cloth. Avoid exposing it to extreme temperatures and water for long periods. Also, when not in use, store the battery in a cool and dry place. This way, your headlamp will be ready for your next outdoor adventure.