Finishing the Cornice Board
When sanding the wood, make sure you sand off any paint drips on the wood so the wallpaper lays smoothly.
Wallpaper Width
On our first cornice board, we used a 7-inch wide wallpaper boarder. This seems to work better than the 5-inch wide border we used on the second cornice board. It is easier to cover all the hardware on the window blind.
Wallpaper Color
We found that a darker color with more contrast works better than a light color, especially if you have light colored walls and blinds.
Gluing Wallpaper
If the edges of the wallpaper do not stick well, you can use some Elmer's White Glue to glue the wallpaper to the wood securely.
Hanging the Cornice Board
Make sure your "L" brackets are the right length. You want to be able to cover the window hardware but you do not want the "L" brackets to be so long as to hang over the window itself.