Love your quilt; it is definitely the winner.
I make my sleeve about 9 inches wide by length of the quilt and on the short ends I shave an angle from one corner to the other corner going inward by 1/2 inch so that one sided is shorter than the other side. Then I hem the short sides and fold in half making a sharp crease. I now have a recessed hem under the top hem on both ends of my sleeve. This keeps the side hems from being on top of each other. I sew the raw edges onto the quilt when I do the binding. Then when I am sewing the binding down by hand, I sew the sides and bottom parts of the sleeve to the quilt leaving a small gap (lift up the bottom center crease about 1/2 inch) for the pole. Hope this makes sense.
Others have posted tutes and they are good too.
Rumbols