Full-face CPAP masks usually have four parts: the frame, the cushions, the headgear, and the tubing attachment, each of which can be taken apart and cleaned separately. You should wipe down the cushions every morning. Many people find specialty CPAP wipes convenient for this purpose.
The headgear, mask frame, and tubing attachment need cleaning once a week using warm water and mild detergent. Be sure to rinse and dry each part fully before reassembling the mask. Note that memory foam cushions shouldn’t be submerged in water and just require daily wipedowns. Consult the mask’s user manual for specific cleaning recommendations and replacement schedules.