Remove the cushions from the couch. Center each cushion face-down on a twin-sized flat sheet and fold the sides of the fabric up and over the sides of the cushion.
Fold the extra fabric on the bottom of the cushions neatly and pin down using a twist-in upholstery pin every 5 inches.
Drape a king- or queen-sized flat sheet over the frame of the couch. Depending on the size of your couch, you may need to use more than one sheet over the couch to completely cover all areas.
Smooth the sheet or sheets over the frame and tuck the sheets into the sides and back of the frame.
Secure the sheet or sheets to the couch by inserting twist-in upholstery pins every 5 inches around the bottom of the couch and on the edges of the seat area.
Place the covered cushions back on the couch.