Here’s something I saw on another site (don’t remember where). Take a photo of your face facing forward, split it down the middle, separate the left and rights sides into new images and the complete those images by flipping them.
You’ll wind up with three images: image one – your original face photo, image two – your face as it would look if your left side was mirrored to your right, image three – your face as it would look if your right side was mirrored to your left.
Interesting results and it makes you see the differences in the sides of your face. My “left face” definitely looks a little more plump than my right face.