Leaving a few inches spare take your tape measure in both hands and pull each side towards each side towards its self.
using a needle sew the centres together, alternativly you can use some glue
Repeat this step untill you have 5 loops, sewing or guing each time.
now you need to create the second layer of loops.
These loops need to be smaller than the ones below, 4 should be plenty
Once you are satisfied with the fullness of the brooch cut off the excess leaving enough tape to fold over the into a normal loop and stitch/ glue the underside.
With the excess strip, glue/sew this to the back of the brooch then attach a brooch back