https://www.skillshare.com/classes/Watercolor-Portrait-from-Sketch-to-Final-Painting/484267956

Watercolor can be a tricky medium, but with some tips and practice, you can achieve beautiful results!

This class will teach you how to create great watercolor portraits from photo references from start to finish, with lots of valuable information on technique and materials. 
While no prior skills are strictly needed, I only give a primer on drawing and one demo of the drawing process. Thus, I believe students who already draw to some extent will probably benefit the most from the classes.