Plan: 

• Make a mini version.

Material to test:

• 108" Spring steel cut from a 1/8" flat steel fish tape (Amazon link)  This was eyeballed as "about this much" since it was for the test

Goal:  

1. Test how to attach the ends of the spring steel.  We don't want them coming loose with time and tearing the fabric.
2. Plan how to attach the main fabric to the loop.  The trick will be to keep the fabric tight when it's opened.