Remove the original cushion from the antique couch and examine for moth or other insect damage. Vacuum the antique couch and cushions. Measure the height and width of the couch, using a measuring tape, to ensure you'll have enough material.
Remove the old upholstery. Pull out the staples attaching the fabric into the edge of the couch, using needle-nose pliers. Use a carpenter’s hammer, and take the claw-tooth end to remove all old nails, being careful to not pull the nail too roughly from the frame.
Place the new upholstery over the old fabric. Use the old fabric as a template for the new fabric, unless the new fabric is already pre-measured to fit the couch. Place the new upholstery over the couch, and pin in place with upholstery pins. Cut away the excess upholstery with a pair of upholstery scissors.
Attach the upholstery. Start at the back part of the couch. Begin from the bottom and work upward, stretching the upholstery, pulling it tight up over the back of the couch to the front. Secure the upholstery with a staple gun into the frame of the wood of the couch, making sure that the upholstery is smooth, pulled tight and not bunched in corners.
Reupholster the arms of the antique couch. Take a heated glue gun and apply glue to piping or batting, and attach to the edge of the couch, if the original piping or batting is to be replaced.