To charge your massager, insert the charging cable into the charging port marked DC and plug it into a power source. The buttons will light up to indicate that the device is charging. When the light stops, the device is fully charged. *An important note: While the charging port looks tiny, the charger pin fits perfectly, so just pierce it in there properly till the changing pin is completely inserted and no longer visible externally. (The charging port is designed so securely, in order to ensure the device’s water resistance.) If you don’t insert the charging cable’s pin in completely, it won’t charge— make sure the charging pin is fully inserted!