Structure

• Wood is often used in the construction of cornice boards. Choose plywood or medium-density fiberboard (MDF) when spanning large windows. Select Styrofoam for very small windows only. Styrofoam is not rigid or durable enough for long cornice boards. Cut wood into the desired length and shape with a hacksaw. Use an electric carving knife to cut Styrofoam.
  
  

Padding

• Pad the cornice structure with padding. Choose poly fill or quilt batting and attach it to the cornice board. The more padding used, the softer and fuller the cornice board. Staple batting to wood. Duct tape it to Styrofoam to secure it into place.
  
  

Fabric

• Prints that coordinate or contrast with the draperies make a beautiful option for cornice boards.NA/Photos.com/Getty Images
  
  Cover the cornice board with decorative fabric. Inexpensive quilting fabric is an acceptable alternative to more costly upholstery fabric. Avoid stripes, checks and plaids unless you have made several cornice boards. These patterns are challenging to keep perfectly straight during the upholstery process. Wrap the fabric tightly around the cornice board and staple or duct tape it to the back. If the back of the cornice board is visible, cover it with white fabric to hide any raw edges.
  
  

Trim

• Trim the edges with ribbon. Use flat, decorative ribbon to outline the shape of the cornice board. Add ribbon with fringe and tassels along the bottom edge for more interest. Skip the ribbon and use buttons to replicate nail head trim work. Embellish with bows or silk flowers to customize the cornice board.