Take apart your sofa’s cushions and back pillows. Take out the stuffing and turn the covers inside out.
Purchase the same type of stuffing and foam used in the cushions and back pillows if they are no longer in good condition. If they are reusable, use them again.
Toss them in the wash or refresh them with a good cleaning using an upholstery deep cleaner.
Toss them in the dryer or set them in a covered area outside to air dry.
Use the old coverings as a template or pattern for the new fabric.
Place the old foam pieces onto the new foam and trace their outline onto the new foam with a permanent marker.
Cut out each piece along the lines through the foam with an electric carving knife. Set each cushion aside.
Spread the new fabric on the work surface and fold it to create two layers.
Lay the old sofa cushion and back pillow covers onto the fabric. Mark their outline 1 inch from the edge of the old covers onto the new fabric with a fabric marker, permanent marker or simply outline it with straight pins.
Cut out the new covers along the lines.
Follow the same pattern as the old cushion covers. Lay the fabric pieces with right sides together and pin the edges of the fabric all around. Sew a zipper along the back seam if the original cover had a zipper. Try recycling the old zippers and sew them into the new covers.
Snip off the excess fabric at each corner between the seam and the fabric edge. This fabric tends to bunch up at the corners.
Press the seams flat and then turn the covers inside out.
Match up each piece of foam to the right seat cushion.
Push the foam into the seat cushion all the way into each corner. Smooth the fabric cover over the foam.
Stuff the back pillow covers with the same type of stuffing as the original ones. Push the stuffing evenly throughout the cover until the back pillow has a good shape.
Sew the opening closed or zip the zipper closed. Place your new seat cushions and back pillows on your sofa.