- 1). Measure the length and width of each side of your cushion using a measuring tape.
- 2). Add an inch to both the length and the width measurement for each side of your cushion. For instance, if your cushion's width is 16, it should become 17. If the length is 24, it should become 25.
- 3). Add an additional inch to the width measurement of the side where you plan to put the zipper. The zipper is typically located on the back of standard cushions, like throw pillows, or on the end of longer cushions, like lounge chair cushions.
- 4). Use a straightedge and a pair of scissors or a fabric trimmer to cut a piece of fabric to the new measurements for each side.
- 5). Cut the piece of fabric for the side that will contain the zipper in half. Fold the rough fabric edge over and press it using an iron. Place the zipper under the fabric, zipper pull side up. Position the fabric, so you only see as much of the zipper as you want to see in your finished product. Pin the fabric to the fabric of the zipper using straight pins. Sew the fabric to the fabric on the side of the zipper. Repeat the process with the piece of fabric for the other half of the back. Zip the zipper almost completely closed. Pin the top of the zipper closed, so the fabric sits the way it will when the zipper is completely closed.
- 6). Place the piece of fabric for the largest side back down on a table. Pin all the other pieces that will make up the sides of your slip cover, except for the piece with the zipper, to the large piece. Sew the other pieces to the large piece.
- 7). Sew the unattached edges of your large fabric piece together to create a fabric "box." Your cushion slip cover should be completely constructed except for the side with the zipper.
- 8). Place the piece of fabric with the zipper, fabric side down, on top of your slip cover. The slip cover should be fabric side up. Pin one edge of the zipper side of the slip cover to the corresponding slip cover edge of the larger slip cover piece. Sew it together. Repeat the process for the other four sides.
- 9). Remove the straight pin at the top of the zipper. Use your finger to push the zipper open. Turn the cushion right side out, so the fabric side faces out. Zip the cushion. Stitch together the fabric at the top of the zipper to create a seam, if needed. You should still be able to unzip the zipper.
- 10
Put your original cushion inside your slip cover.
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