For the width I followed Ray Jardines recommendation for want of anything else. He states that the ideal width of the draft stopper is 7.25", but that it can be made wider or narrower. He has the draft stopper on both sides and the head end. I didn't like it on the head end since it kept flopping in my face and so have it only on the sides. Also, I put a draw string on the head end to cinch the quilt around the neck and seal it so that a draft stopper there wasn't needed. The draw string keeps the fabric out of my face.