To charge an elf bar, you need to place the bar on a flat surface. Then, press the power button on the bottom of the bar to turn it on. The battery indicator will light up and display the current charge level. If the bar is low on charge, plug it into a power outlet using the USB cable provided. The bar will automatically start charging, and the battery indicator will show the charging progress. Once the bar is fully charged, unplug it from the outlet and store it in a safe place. It's important to remember to charge your elf bar regularly to ensure it's always ready for use.