Start with constructing the forms.
Then shade following the 5-step pattern (highlight, light, shadow, reflected light, drop shadow).
First - practice drawing and shading each shape. use the printout of the presentation above as a reference (printout).
Use a 18x12 drawing paper. Divide the paper into 6 areas.
Construct the forms.
Mark your light source. Shade the forms using the Chiaroscuro pattern: