Draw a horizontal rectangle for the seat base
Add two vertical lines at the left and right ends for the armrests
Draw a tall curved or rectangular backrest above the seat base
Connect the armrests to the backrest with smooth lines
Add two front legs beneath the seat base
Add two back legs beneath the backrest area
Round the corners slightly for a softer sofa shape
Draw cushion lines on the seat and backrest
Add seams or stitching details if desired
Erase extra guide lines
Outline the final sofa shape clearly
Shade or color the sofa