So I took some yarn from my stash and without a particular pattern, I started with a chain of 22 and worked double crochet stitches into a scarf-like shape until it was long enough to fit in the glasses when folded.
The elastic of one of my pearly hair baubles was worn out, but the pearl beads were too good to throw away, so I started using some of them as decoration and added crochet flowers, frilly trim and cord. Finished! Overall this project took me about 2 hours to complete.
This is a great project for a beginner, and you can use your own imagination when it comes to colour, yarn type and decoration. All I'd suggest is using a yarn for needles up to 4mm; thicker yarns would make the glasses case too bulky. Double crochet stitches make the case material nicely stiff, offering more protection for contents.
Yarn used: Sirdar Balmoral
Shade 476, Damask, and 487, Royal Purple, for flowers, trim and cord