There is nothing you have to do, simply leave it plugged in to a power source.  Leave your devices (eg. router and Fibre box) connected to the UPS to ensure it draws enough power to keep charged. The UPS will automatically and seamlessly keep your devices powered during power outages. UPS (Uninterruptible Power Supply) provides your electronic devices with seamless power when there’s a power outage. They also help to protect your devices from getting damaged during power surges, short circuits and other irregularities in electric supply.