Here's a nice one for you:
This is called a cornice, or an upholstered cornice.
Hi Lois, here's another great video that will show you how - https://www.youtube.com/watch?v=57bNYhxXjGg
Hi Lois, I love the look of fabric covered wood cornices, however they can be very heavy to put up. I wanted to show you this other option:
These are made out of foam and really look great!
Here is a nice video tutorial for you: https://www.youtube.com/watch?v=J8WIQlHaw_E
Here's an idea that only costs $15:
Hello building them out of insulation foam sheets could be another option they could be glue gun together and mounted on an L bracket. Lumber has gotten quite expensive we just spent $50 on four boards to make a table yesterday.
Hi! ...if you're covering with cloth, I would use foam board. It's way cheaper and SO much easier to install. Here's how!
Make a frame the width you want the Valence Pelmet to be DF or Hardboard or plywood in the shape you desire. Fit a bracket either side of the top of the window and one other in the centre. One you have covered the valence/pelmet., rest it in place on the brackets. Enjoy
Hi Lois, here are a few ideas, hope they help you out
Here is how to build a simple wooden valance: https://www.youtube.com/watch?v=oURiXbpegXo
Depending on the length and size of your cornice, foam board might not be sufficiently robust to have the cornice keep its shape once hung up on the wall, which may result in it sagging or bowing.
Here is a tutorial using wood:
Hi Lois. You can build a structure in the shape of a L. Cover it with foam and then batting to give it a look of softness. You can use a bread knife to easily cut the foam. Use a spray adhesive to attach the foam and batting to the wood. Then cover it with the fabric of your choice using a staple gun. Begin by pulling the fabric from the center of each side, and then completing it by attaching the rest of the fabric. Cut off any excess fabric. Once complete hang it by using L brackets into the studs inside your wall. Good luck Lois.
Plywood cut to the width of the area you want to cover can be attached with side pieces the depth you want and attached to the wall on both sides of the window. You can add batting and fabric. I tried making them from foam board, insulation board and even cardboard at different times, but, was never satisfied with them. Plywood and any other wood requires more support, but will look better, longer. Good luck and stay safe!
How to build a wooden valance https://www.hgtv.com/design/decorating/window-treatments/how-to-build-a-wooden-window-valance