Today has been a very productive day for me. I finished up the blue glass painting that was started last night, and I began a new painting. It is on a 16" x 12" panel.
I started off by drawing the above lines on the board with charcoal and a ruler. These help with composition and placement. Notice in the drawing below the placement of the head within the top-middle diamond shape and that the model's line of sight follows the triangle-shape through the bottom right-hand corner.
Here everything has been drawn in with charcoal and some shading indicated. I use charcoal instead of graphite because graphite may become visible through the paint surface as an oil painting ages.
With the drawing complete, I 'ink in' the contour lines with oil paint that has been diluted with OMS. In this instance I used raw umber, though burnt umber or asphaltum yield similar results.
After the contours are set, I generally begin painting in the darkest-darks and/or the background. Here you can see a couple shadow values were blocked in before the end of the session. I plan to work on this again tomorrow and will try to take more step-by-step pictures to post.