I recently finished this cute little cushion. I found the free pattern for this on this website.
It is actually a part of and already finished CAL. If you click the link it will take you to the first part and you'll automatically see the link to part 2 then.
I bought the cushion for £3 in Hobbycraft. You can find it here and I used acrylic yarn for it. I think that is better, because it stretches more than cotton and you need to stretch it quite a bit to make it fit around the cushion.