So far I've had the most success with a simple picture of me stretching when I was tired one morning and sister had my phone and was bored. I think the main feature is that you can see my forearms are veiny. But most of my face is obscured by sunglasses, may hair is covered by a wool hat, and I'm generally being tired, sleepy, and uninteresting.
Pic in question: http://instagram.com/p/lm5FNjkxp1/?modal=true