My DH made mine the same way you made yours. It is on an OLD wooden ironing board I got from my m-i-l. I cover it with a double layer of muslin and some thin batting inside and then I put tacks in to hold it down. They come out easier than staples, which I can't seem to get through the wood, when I want to wash the muslin. LOVE IT!
Chris G.
aka busiacam