The secret to a perfect selfie? Add some math.
The best portraits incorporate something called a Fibonacci Spiral. It spreads like a Nautilus shell, touching each side of a rectangle that is 1.618 times deeper than it is wide. On the Mona Lisa, for example, the spiral begins at her wrist, at the bottom of the image, and then extends over her shoulder, into the background, before crossing the top of her head. Then it tightens, touching her chin, her dimple, and the tip of her nose. That centers the image in a way that makes the eyes seem to follow you.