Wear a medical procedure mask (surgical mask) underneath a cloth mask. This gives you better protection than cloth mask by itself or a medical or the surgical mask by itself. This has been proven by laboratory studies.
Do not combine two surgical masks to create a “double mask.” - surgical masks are NOT designed to make a good overlap.
Do not combine a KN95 mask with any other masks - either on top of it or underneath - you should wear only ONE KN95 mask at anytime.