Diamond Fabric

What is the easiest way to hang curtains on a diamond shaped window?

Maybe diamond isn't the best word...my mind is drawing a blank...basically a square rotated so the points are at the top and bottom. I'm NOT a sewer, and I have cut fabric and used my glue gun to make seams at the edges--now I'm not sure of how to hang it besides using penny nails to attach the fabric to each corner? I'd prefer a way to hang it so I can open it half way or partially to let sun in...
Note: The window is in a rental home, and I won't be here for much more than 6 mos. to 1 year, so custom made is out of the question. And the only reason i want to cover it occasionally is that it is between my bedroom and bathroom and i tend to walk by alot in the nude, and well, i'm not into exhibitionism....

This is such a FANTASTIC window why would you want to cover it up???

If I were you and had this gorgeous piece of art in my home, I would measure the square, then go to a custom iron shop or maybe a stained glass shop and have either a custom stained glass piece that can be inserted into your window to filter the light (maybe your initials or favorite animal, something personal) or, maybe a custom scrollwork rot iron piece.

Then, once you filter the light, I take your fabric and fold it in half. At the center, grab hold of the fabric (like your choking something), put a hair elastic around it. Then floof the top part of the pony to resemble a bow. Then tack your bow above the top point. Tack a nail or something non noticeable to the two side points and let the fabric just drape over the sides.

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