Save yourself the trouble and cost of matching up different pieces when making a loose cover for a sofa or chair; choose a solid-colour fabric or one with a small overall pattern. Avoid stripes, checks, large patterns and fabrics with a one-way nap.
Don't use your old sheets as loose covers; get new ones with a factory finish that will protect them from soil and stains. After washing, apply a fabric protector.
Buy everything you need at the same time so that you can be sure the sheets come from the same dye lot and match perfectly.
Hide worn upholstery under a bed-spread, quilt, sheet or shawl. For a more finished effect, drape the fabric over the frame, tuck it into the inside crevices and pin it in place with a safety pin. At the outside comers, cut quarter circles to remove the excess cloth; stitch down the cut edge, then attach ties, grommets, Velcro or tape with plastic press-studs to pull the remaining cloth tight. Wrap loose cushions separately.