Step #1
Draw a rectangle like prism as shown.
Step #2
Draw the same shape as above but slightly small in size.
Step #3
Enhance the shape created above in step 1.
Step #4
Enhance the shape created in step 2.
Step #5
Draw four small lines at one side of the rectangle.
Step #6
Repeat the above step.
Step #7
Enhance the drawing as shown.
Step #8
Make necessary improvements to complete the drawing.