Dear Rui,
You are off to a good start, with a very strong likeness. At this point the major things you might look for are the shapes in the hair that are different in value, so you can develop a feel for the way it flows; also, check the placement of the eyebrow on our left.
There are a couple of things that will make this portrait difficult: first and most important, the photo has been taken with a flash attachment, and that's why you have no real light and shadow patterns to work with. The flash also works against being able to see differences in color and temperature. Second, it's very difficult to paint a wide smile with lots of gum showing...have you seen the thread here on
painting teeth?
Best wishes,
Threaded Mode
