Three major principles:
, Mirror and not being on the toilet. Toilet discharge of filth, do not have to "mirror", as long as you don't see on the toilet mirror, mirror see toilet is reasonable.
Second, toilets, mirrors are not facing the bathroom door.
Third, the bathroom has a window, and the window must be open. Bathroom with window, and Windows always open, noxious gas, moisture can be discharged out of the window, keep the air dry and fresh.