Measure the floor to ceiling height, keeping in mind that the canopy will hang about 6 to 12 inches from the ceiling.
Purchase tulle in an amount that is twice the length of the height of the canopy, plus 2 extra feet. Purchase a large embroidery hoop 17 or 20 inches in diameter, and pull the inner (smaller) circle out of the hoop.
Lay out the tulle on a clean surface. Place the inner circle of the embroidery hoop underneath the middle of the tulle and the larger hoop on top of the smaller hoop (and over the tulle), but do not push down. Pull 2 feet of the tulle through the middle of the large hoop. Push down on the larger hoop to hold the fabric in place.
Slide a fishing line or thin ribbon through the top portion of tulle that was pulled through the hoop (close to the top). Tie the line or ribbon into a double knot to ensure it stays in place.
Measure the ceiling to find where you want your canopy to go. Ideally, the middle of the canopy hoop should be directly above your face when you are laying in bed. For a 17-inch hoop, that's about 10 inches from the wall; for the 20-inch hoop, about 13 inches. Screw the screw hook into the location.
Bring the hoop with the attached tulle up to the hook. Tie the ribbon or line onto the hook, using a decorative bow if desired. Turn the hoop so that the canopy opening is facing the front of the bed.