Take pictures of your sleeper sofa to use as references when it is time to put it back together. Photograph it from all angles.
Measure the existing sofa drapery with the tape measure. Measure the sofa's length, width and depth to ensure you have plenty of fabric.
Buy your fabric, adding roughly one foot to the measurements to allow for hems and seams. Choose fabric colors and textures as according to whether you want the sofa to be vibrant or soothing. If you are going to allow pets on your reupholstered sofa, use fabric that will withstand the wear and tear of animals.
Remove the old sofa fabric by gently tearing it back. Use a staple remover as necessary. Use the scissors to gently cut off or detach fabric portions that are glued. Retain zippers, if any, on the old fabric.
Check the stuffing of the sofa. If it is soft and intact, retain it; otherwise, replace it. Position the stuffing using a hammer and nails or upholstery pins.
Cut the new fabric with the scissors using the old fabric as a guide. Allow enough margin to accommodate pinning the fabric to the sofa. Use the sewing machine to sew the zippers to the new fabric, guided by the old fabric.
Cover the sofa with the new fabric. Use the photograph as a guide to pin or glue the fabric correctly at the required locations. Trim any extra fabric. Refold the upholstered sofa to ensure it's functional.