The following steps describe my strategy.
Step 1: Laundry
Step 2: Crystal Curtain
Dark blue velvet
Sheer silver fabric for the moon
About 2 dozen chandelier crystals of varying sizes
Curtain hardware (rods, rings, etc)
I made a simple curtain with dark blue velvet. The width of the cloth is approximately two times the width of the window so it is still wavy when the curtains are closed. I sewed simple pleats on top, so the side attached to the rings has the same width as the curtain rod. If you wanted to you could make curtains which are flat when they are closed are closed (like roman shades), but in that case, unless you line the fabric you won't cut out as much light or heat. If you can't sew you can just have curtains made, but honestly, it's really easy and it's much cheaper even if you need to buy a sewing machine.
After I finished the curtains I spread them on the floor and cut out little x's where I wanted the stars. I sewed the flaps down by hand, then sewed on the chandelier crystals I'd bought at the flea market. Use polyester rather than cotton thread -- it will last much longer.
I used a plate to mark the shape of the moon, cut it out and sewed on the sheer fabric. You need it to keep the curtain hanging nicely, however, the sheer fabric is much more fragile than the velvet and will not last as long. The sun dissolved my original moon (after about 7 years), and although I have more fabric I have yet to get around to replacing it: if you look carefully at the second picture you will see that the curtain doesn't hang properly under the moon. That's because now it's just an empty circle.
The curtains work beautifully. They keep the room cool, and the babies used to go around chasing all the rainbows the stars would throw around the room. Once in a while I even catch myself playing with the rainbows on my hands rather than doing my work....