Sketch the shoulder, upper arm, elbow, forearm, and hand as simple shapes
Mark the arm’s gesture and direction with a light center line
Block in the upper arm as a cylinder or tapered form
Block in the forearm as a second tapered form
Place the elbow between the upper arm and forearm
Indicate the wrist as a smaller transition shape
Add the hand shape at the end of the wrist
Refine the outer contour of the arm
Define major muscle groups and bony landmarks
Adjust proportions and angles for the pose
Clean up construction lines
Add final linework and shading