Estimate how much fabric you will need to recover your fixed seat cushion. Many places that sell upholstery have charts that help with this estimation.
Consider the wear and tear on your fixed seat cushion. Do you have children or pets? Is your chair used a great deal? How long do you want this fabric cushion to last? Heavier upholstery fabric will last longer and is usually more stain-resistant but will be harder to maneuver when reupholstering the chair. Lighter fabrics are easier to work with but will show signs of wear much sooner.
Purchase the appropriate amount of fabric and welting (cloth that is used to trim the edges of your chair) or trim.
Remove the trim or welting from around the base of the upholstered part of the chair.
Remove the staples or tacks holding the upholstery to the chair with the needle-nose pliers. Try not to rip the fabric, as this will become your pattern piece.
Lay the old piece of upholstery out, right side down, on a flat surface. Remove any stitching in the upholstery so that the piece can be laid entirely flat. Set this piece aside.
Lay out the new upholstery fabric, right side down, on a flat surface.
Lay the old piece of upholstery on top of the new upholstery, right side down.
Trace around the old piece of upholstery fabric, using it as a pattern. Mark any places that have been folded or any notches that will need to be stitched.
Cut out the new piece of upholstery fabric.
Sew any corners or darts that need to be stitched. Trim any excess seam allowance, if necessary.
Replace the batting or foam on the seat of the chair.
Slide the new cushion cover over the batting and settle it onto the framework so that it can be attached to the frame. Check all corners to make sure they line up correctly.
Staple or tack the new cushion cover onto the frame of the chair. Pull evenly on opposite sides of the new cushion cover to avoid wrinkles. Trim excess fabric away from underneath the staples
Run a bead of hot melt glue around the stapled area.
Press the welting or trim onto the hot melt glue to secure the trim, and cover the raw edge of the fabric and staples.