Here is how I did it:
1.Get a cushion inner the size you want. Have a shirt in the material, colour and style you want. Make sure it is a button through shirt not a pull on.
|measure shirt for cutting|
3. Sew the top seam only so that the material becomes a oblong.
4. Add all the embellishments that you want. Sew them along the full length of the material and then it will cover both sides of the finished cushion.
|Back - with a perfect opening|
5. Fold the trimmed material in half along current seam line - right sides together. Sew around the other three sides. Then unbutton the buttons, turn inside out and press. Viola your finished cushion. With a perfect opening, professional button holes all matching up - without having to do the hard work yourself.