To make a cushion for a bench, the first thing is to make sure the foam is cut to fit the seat.
Once cut, lay out the fabric and place the cushion foam on the fabric. Draw stitch lines with chalk, leaving enough stitch room to fold around the cushion and up, which should cover the sides with an extended 1″ to 1 1/2″ sewing room. Cut the fabric.
Then cut the top with a 1″ to 1 1/2″ overhang that will attach to the bottom. Make bias piping with a cord and choice of fabric as your bias tape. Use a zipper pedal so that the stitch is close to the cord (rope). I made a matching button with the same material which I used fabric from the curtain I resized to fit the window so that it would match the décor.
When piping is sewn, pin it to the bottom fabric while also shaping to the foam to create a tight fit. Sew the piping to the bottom.
Turn the fabric inside out and place foam back on. Place top material wrong side up. Pin.
Sew it using a zipper foot pedal. Leave the back side unsewn for last. When sewn, pull the foam out and turn your fabric right side out and place the foam back in. Hand stitch the back-end to close up the cushion.
To view the bench for which the cushion belongs on go to – Turning a TV Stand into a Bench