I used a 24x66 inch piece of 3/4 inch plywood covered with a doubled wool batting and then with muslin. I pulled the batting tight and taped it down temporarily while I pulled the muslin tight and stapled the muslin. I figured I'd redo the muslin at some point but not the batting so didn't staple the bat. I'm going to make an elastic cover out of the silver ironing board fabric one of these days....just haven't gotten around to it! The 3/4 inch plywood is heavy enough to 'stay put' and I don't worry about it warping.