Remove all of the original upholstery from the back and seat of the rocking chair. For some chairs, this may involve unscrewing the back and seat to get to the edges of the upholstery. Other rockers may have the fabric stapled directly to the chair seat or back. Try not to damage the original upholstery.
Inspect the padding on the chair. If it is moldy, dirty or too thin, replace it with new polyester foam. Cut the foam to fit on the back and seat of the rocker and glue it in place with craft glue.
Lay the original upholstery pieces over your new fabric and cut around the pieces.
Place the fabric pieces over the foam and staple or nail the fabric in place around the chair back and seat. Pull the fabric tight to prevent sagging and wrinkles.
Return the chair back and seat to the chair and screw it back in place. Trim off any excess fabric from under the seat.