laying the steps on their side and drawing around them, onto the fabric. cut one more piece that is the size of the bottom of the steps. cut the center out of the bottom fabric so it will look somewhat like a picture frame, with fabric going around the perimeter of the bottom, but no fabric in the center.
stitch the side pieces to the top step piece, then attach the bottom. sew sixteenth-inch elastic around the opening on the underside. this will allow you to stretch the fabric on and off of the steps.
another quick and easy step method, although not quite as safe for people, is made from concrete 