After 5-6 uses or every 3-5 days: 1. Turn off the diffuser and then pull out the plug. 2. Remove the cover. 3. Empty the water from the tank, preventing water from entering the air intake. 4. Spray some kitchen degreaser into the water tank and wait a few minutes; use a cotton swab to clean the ultrasound. Then rinse with warm water and dry it with a clean cloth. 5. Keep the speaker clean and dry if you don’t use it for a long time.