Judy, if you want this mounted on a board, you would have to add a backdrop/skirt to the board like we have on the Kasey or Emily Patterns. Then you could just screw the finials/knobs into the face of the board to attach the valance to the board or use a staple gun.
All of the instructions for adding to the width are included in the pattern. Basically you would just add additional "swag" & "horn" sections.