Place a plan at top.
Draw Picture Plane (PP) and
Center Line (CL).
Decide Station Point (SP) at about twice the dimension of the plan object.
Draw two parallel lines to Picture Plane (PP).
Draw Ground Line
You can place this line at any location.
Draw Horizon Line (HL).
Decide the height of your eye from GL.
Bring lines down from PP for Vanishing Point Left (VP-L) and Vanishing Point Right (VP-R).
Connect lines to Vanishing
Intersection of CL/GL to VP-L and VP-R.
Intersection of Object Height and CL to VP-L and VP-R.
Connect SP to the corners of the box.
Draw lines down from PP where lines connecting SP and the box intersect.