It's hard to decide which is the bigger eyesore: an exposed box spring or some of the froufrou dust ruffles currently on the market. One easy, low-cost solution is to cover the box spring with a drape of rectangular fabric. A tablecloth, bedsheet, or any interesting cloth will do the job nicely. Even better, it will be a cinch to wash and iron. If you use a sheet, choose one that is the same size as the bed: a single for a single bed, a queen for a queen. For a tablecloth or fabric, determine the correct width by doubling the height of the box spring and adding its width plus 6 inches. Calculate the length by doubling the height of the box spring, then adding its length plus 6 inches. This creates a rectangle of fabric that covers the box spring and hangs down an extra 2 inches all the way around, after you've sewn a 1-inch hem.
New Bed Skirt
Martha Stewart Living, November 1994