Here it is:
Cut one piece of home decor med. weight fabric to 42" x 47". Fold in half (right sides together), pin the 47" length, sew it and then flip it
Now fold a 1inch ish hem around both edges, pin and sew.
Flatten out and measure 2 inches from the top (I made a pencil mark every 4-5 inches or so), pin and stitch all along the edge (this is where your dowel will go into)
and... DONE! Easy peasy! With no awkward looking hems and very little brain work involved. Perfect rainy day project in my humble opinion since I finished it within and hour and now get to feel accomplished and have time to read my book... or sew something else... or clean the house