Stillness
When I was in high school, I focused really hard on being very still and moving slowly. I thought it made me seem more dominant and powerful, so I put a lot of energy into mastering it.
Nowadays, paying more attention when I'm out and hanging with girls, I'm realizing this is a big thing, nonverbally. Women are very attuned to how still you are. Being still radiates power.

I'm almost finished reading a great book, called The Drunkard's Walk: How Randomness Rules Our Lives, by Leonard Mlodinow. Its premise is that all these things we attribute to skill are, most often, due to sheer luck.