Push the cover Back, take out the sponge, soak it in water and swing it in air and then put it back in its place.
The effect will be better if you refrigerate the sonaking sponge.
You can also drop a few drops of perfume in sponge, which can blow out the charming fragrance with cool breeze.
Charging state and working state show red light. Charging full shows blue light.
Power Source: Battery