Curtans/Valances are fun, Pick what speaks to you. Then the pattern desired. So much better when you have on the windows that are pleasing to you, and remember if they don't work out can always make a Quilt out of the oops !!:)
Have looked thru mail order for the ideas straight, loops, frilly, measure window then X 2 or 3 on the with depending on how full you want them, then can line or not, so many options, Make sure to buy extra fabric, sure enough will want a Runner, Pillow, Potholder, Chair cushon to match.
Have Fun with it, no Curtain police either !! LOL
Sheets work great also :)