The pocket square.

1. Angle your pocket square up toward your left shoulder, it is more flattering that way as it accentuates the V shape of your body.

2. Regardless how long it took you to do a perfect fold, whether it be the four-point, the triangle, the square or the puff, your pocket square should give the illusion that it was thrust haphazardly into your pocket.  (Even though there was nothing haphazard about it).

Fact credit: The Suit, Nicholas Antongiavanni, p 157.

Image credit: usonline.apc.fr