Measure the chair seat. Add two inches to both the length and width - one inch (for a half-inch seam allowance on each side) plus one inch for the puff factor.
Once you decide on the size, cut two pieces, one front and one back. Stack the pieces together and fold in half. Cut the bottom edge to be rounded.
Cut two ties to be 20"x 2".
If you are using ribbon or trim, skip this step. To make the ties, start by folding your tie in half lengthwise right sides together and press. Stitch all the way along the side and across the top.
Turn the tie right side out. Fold a little of the open in to the inside and stitch across the end, closing up the open end.
Cut tie in half. Repeat with other tie.
Pin your ties in between the front and back piece. The front and back should be right sides together. Pin the ties about an inch and a half in from the sides.Make sure the ties are facing in towards the center of the cushion and the raw edges are lined up at the back. You need two ties on the right side and two at the left on what will be your back seam. Pin it all together. Stitch across the back then pivot and stitch down the side, across the bottom, up the other side and then across the back until right past the left set of ties. You should have an opening left in the back between the ties for stuffing.
Clip corners and curves close to the seam.
Turn your cushion right side out.
Stuff your cushion with polyfill or other stuffing of your choice. Stitch up the opening in the back with your hand needle and thread using a blind stitch, ladder stitch, or a whip stitch. You can leave your cushion like this or you can add buttons.
To make covered buttons, cut a piece of fabric with the template included in your kit. Then follow the instructions for your kit to assemble the button(s).
Measure and mark where you want your buttons to go. Mark the placement on the front and back of the cushion.
Bring your threaded needle up from the bottom through the marked spot.
Thread the button on the needle and then bring the needle back down through to the back side. Then repeat a few stitches.
Pull the thread tightly so that the button sinks into the pillow. Tie off the thread with a couple of knots.
Clip the excess. Repeat with your other buttons. Finish by tying your cushion to the chair.