for this cushion, you need,
one square piece of hessian
one rectangle piece of fabric for the back
then with the masking tape, make two lines down the middle of the fabric, and paint with white paint, then remove the tape and wait for it to dry.
then with the larger peice of backing fabric, cut in half, fold over the rough edge and stitch with sewing machine, then place on top of cushion making an envelope and stitch all the way around, cut off any excess and turn the right way. Now its done you have your own personalised grain sack look cushion. i stitched around it with the machine twice as hessian is prone to fray and i didnt want it to fall apart.