Before refilling, carefully clean the inside of the original diffuser bottle. We recommend using standard-grade pure alcohol for cleaning. First, remove the used evaporating sticks, then unscrew the diffuser cap. Pour 50–100 ml of standard-grade rubbing alcohol into the original diffuser. Remove the cap from the refill, screw it onto the original diffuser, and swirl the bottle until any dirt or perfume residue has completely loosened from the inside of the bottle. For stubborn residue, we recommend using a bottle brush. Repeat the process if necessary. Then remove the cleaning solution from the bottle and rinse it out. After cleaning, carefully pour the fragrance liquid into the original diffuser. We recommend using a funnel. After filling, screw the lid back onto the original diffuser and insert the evaporating sticks included with the refill; these are essential for optimal fragrance release.