Steps:

1. Measure the window from the outside edges of the surrounding molding. Add four inches to the measurement to determine how much Styrofoam is needed for the cornice.

2. To add scallops or another pattern to the cornice, draw the pattern on paper, and transfer the design onto the Styrofoam. To cut the Styrofoam, use a serrated steak knife coated lightly with candle wax. To smooth the edges, rub them with a scrap of foam.

3. Measure and draw the pocket into which you will tuck the fabric across the top of the front section of the cornice. Then score it lightly with a blunt pencil.

4. Cut a strip of fabric 1/2 inch wider than the pocket measurement and three times the width of the front of the cornice. Then, tuck it into the pocket with a putty knife while shirring the fabric.

5. Cut a piece of flame-retardant batting to fit the area below the pocket. Glue it into the crease with a needle-nose glue gun. Be sure to use low-melt glue when working with Styrofoam. Alcohol will remove any glue that gets on the putty knife.

6. Tuck the main fabric over the batting.

7. Repeat this procedure for the area over the pocket. Then add cording or other trim.

8. Attach the side pieces to the front piece with wood picks as toothpicks are too flimsy. Add a drop of glue to the end of each pick before pressing it into the foam. Be sure to work on a flat surface.

9. Wrap the cornice with fabric as if wrapping a package, clipping and gluing at curves. Then line the cornice with fabric.