I’ve gotten to the point where I can put down a vague representation of a figure,  such as this one, when I’m in public and my "model" is sitting still. But I need more information about how hands look in different positions. I’ve had the most practice drawing my own left hand, but not much more. Also the structure of the head in different positions, and the figure itself. Practice. I used Prismacolor water soluble graphite and later, at home, did the washes. Adding water fixes the graphite so it doesn’t smear.