While ago, I had this two large cushions I got from a couple who were moving out.
Bought striped fabric from IKEA, they're nice and durable and have so many cute designs to choose from. Check out more selections!
Making pillow case is one of good practice for sewing. Cut the fabric following the dimension of the cushion. For zipper, I reused the zipper from the old cushion case.
With the old pillow case I cut them into four squares and sew the edges and stitched inside the square. Reuse your unused fabric into cleaning cloth so you never have to buy them!