The best design wall is a sheet or two (4x8) depending on if you want to put up a whole quilt on it at one time - and cover it with flannel and lean it against the wall at a slight angle - so it stands against the wall - a friend of mine has done this and it works for any size quilting you care to do - she has done patchwork looking pillow tops, to king sized quilt - and it works so well, as if it sets right by your machine - you can take the blocks off the design wall in order that you want to sew them - no mess ups and accuracy each time - it gives you a great idea of how your quilt will look when sewn together and you can move it easily enough to have the right light shine on it for true color coordination... I just moved into a big house with huge rooms and plan to make one of these for my one wall - so basically I'm setting up a whole new sewing room with all the ideas I've acquired from many wonderful people on this site showing their sewingrooms or telling what they've done... good luck - have fun!