Rinse, pat dry, dry burn (pulse the fire button until the coil glows and you hear no sizzling). This will burn off any gunk/build up on the coil and wick, and restore flavor. Eventually the silica will break down and you will need to replace the clearo/head, but a good clean and dry burn can significantly improve its life. How often you do this depends on the power seen at the coil, your draw, and the viscosity/chemical content (i.e. sugar) of the
juice.