Draw the outer walls or boundary of the stairwell
Mark the floor opening where the stairs will descend or ascend
Sketch the first landing or platform if there is one
Draw the stair run as a series of evenly spaced steps
Keep the step risers and treads consistent in size
Add the second stair run if the stairwell turns
Include handrails along the open sides
Draw the wall lines following the stair angle
Add the underside of the stairs if visible
Refine the perspective so the stairwell looks dimensional
Erase construction lines
Darken the final outlines