Warm up with fast "driving" contour drawing. I forgot to get a picture.
Continue loosening up with ink and a brush extended with a ruler. You should really feel loose now.
Slow way down. Have your eyes slowly follow the outlines of the subject. Sync your hands with that slow observation. DO NOT LOOK AT THE PAPER. Sync your eyes and hands. SLOW!
Create an accurate contour line drawing by looking at your paper about 25% of the time. Stay SLOW. Keep your hands and eyes synced.
Use the accurate contour line drawing to create a cross-contour line drawing.
Cross contour line describes volume with line.
Sorry, this isn't quite a how to....