Using the Ravemen PR800 is a breeze. First, mount it securely on your bike using the provided bracket. To turn it on, use the wired remote or the main switch on the light. You can cycle through the 5 operating modes according to your needs. When you need to charge your other USB - powered devices, just connect them to the PR800. If you want to use it as a handheld torch, simply detach it from the bracket. As for charging the PR800 itself, plug it into a USB power source with the supplied cable. The charging lights will let you know when it's fully charged. Remember to keep it dry and clean. Avoid exposing it to extreme temperatures. If it gets dirty, gently wipe it with a soft cloth. This way, your PR800 will serve you well for a long time.