Every form is curved and spherical to an extent. Drawing different forms in the portrait, such as the nose, was just an extension of this idea to differently shaped forms.
I build each form by creating curves of gradation. I add one curve next to the previous until the form is laid in. An initial curve of gradation is like the one seen in the cast drawing below.
I added the background with powdered graphite that I diluted with water. The value range was set up in the portrait. I wanted the hair to be the darkest value. To make the background recede, the more narrow value range of the background was drawn in relationship to the darkness of the hair.
Independent Scholar, Graphite, 4 x 5 inches