I created this for a lady from Kuwait I met on Flickr. She posted a photo for me to use as reference.
When I first saw the photo, I knew exactly what I wanted to do with the glasses.
I initially traced the head and facial shapes, which looked rather random and helter-skelter when I finished. I then manipulated the shapes --straightening, rounding, simplifying... trying to unify them, creating a flow with the shapes for a more graphic feel.
I used two different halftone screen sizes for the face and the cap. The sharp, detailed, and close-up photo revealed the man's pores, suggesting to me the halftone screen as how to imitate the effect. The cap was knit, and I thought the bigger halftone screen captured the feel of it well. :)