To make a long story short, my son-in-law's duty station is changing from Schofield Barracks on Oahu to Buckley Air Force Base here in Colorado because of my granddaughter's medical issues. My house is very small and so I'm giving up my bedroom for their little family so they can secure housing and save a little money and am starting to decorate my granddaughter's area.
This mobile is made from fabric I had lying around, some fusible web, bias tape, some hooks, #95 paracord, embroidery floss, and some cheap doodads I picked up at the craft store. It's not perfect and I didn't spend a lot of time on it but I'm pretty sure my granddaughter will like looking at it. Length and width is close to that of standard crib size.
Since the only fabric I had that was large enough was pretty sheer, I used medium weight fusible web to reenforce it because I didn't want the fabric drooping and didn't want it to rip. I then sewed on bias tape to the edges.
I cut the paracord in small strips and attached them to all corners on the back of the fabric. The mobile doesn't actually sit flat against the ceiling; it drapes down.
I used pom-poms, some spiral decorations, and 4th of July styrofoam stars from the craft store and attached them by embroidery floss. You could also use dental floss or fishing line or whatever you have available.
Then placed the small screw-in hooks, attaching one corner at a time so that I could keep it uniform.