Examine the old patio chaise lounge cushion. Is the foam or stuffing in good condition? If not measure the cushion and purchase new foam or stuffing material. Check to be sure the new filler for the cushions is designed for outdoor use. Regular foam can be used if the cushions are being brought in and not left out in the weather.
Measure the old chaise lounge cushion to determine the yardage required. Purchase the required yardage, allow extra for matching stripes or patterns and to make ties to secure cushions to the chaise lounge frame. Purchase fabric. If cushions will be left outside all the time purchase a sun resistant fabric such as Sunbrella.
Make a pattern of the old cushion on newspaper. Allow 1/2 inch on all sides for seam allowances. Measure the length of the old ties and make a note of it.
Cut new foam using the newspaper pattern. Cut the fabric using the pattern drawn. Cut fabric for ties.
Sew the seams of the fabric, leaving one end open for stuffing and turn right side out. Sew the ties and attach to the cushion cover using the same positioning as the old cushion. Sew Velcro to both sides of the open end of the cushion cover.
Stuff the cushion into the cushion cover and fasten the Velcro opening. Attach to the chaise lounge frame with ties.