I still have my mind on this guy. My first portrait of him was a profile view, and I wanted to try painting his full face. I like his expression here, which I interpret as a mixture of caution and intelligence.
When I paint a portrait, getting a likeness that satisfies me usually doesn't happen until the final day. There is lots of fussing over the mouth and eyes, but overall I may spend more time on the non-features, like the folds of skin under the eyes, and the shape of the forehead, cheeks and chin. That's where the real likeness is found.
My recipe for painting a portrait from an image:
1. Paint simultaneously from a color image and a black-and-white version to get both the colors and values right.
2. Paint the entire thing upside down, but frequently turn it right-side up to check results.
3. Paint the details, then when you get tired of them and the painting seems to be going nowhere, move your easel back 12 feet from the images and paint from that distance. It's help pull the portrait together, and the main large shapes will be more apparent.