Here's the one DH and I made a few years ago. Wow, I'm just now noticing the cobwebs at the top....
Anyway, I described what I wanted to DH. He cut 4 pieces out of MDF. He glued and screwed the pieces together, I used his staple gun to attach the poly batting and fabric to the outside. DH attached L brackets to the wall. He put screws with small heads on the inside top of the valance, they fit down and into the holes of the L brackets, so when I want to clean it (which I obviously haven't done in a while), I simply lift it up and off. It's not heavy, just awkward because it's long.
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