You can easily make a cuff bracelet like this one offered at $38 from Anthropologie. Just use hot glue to add embellishments to a plain cuff bracelet. This one has a working watch face to amke it an informal watch/bracelet. I think an old watch face that doesn’t work anymore would still look good in this collage.
You can add pieces of old jewelry, like an earring that has lost its mate, a fancy button, a seashell, a fabric flower, or whatever strikes your fancy. It looks like they covered the cuff with some silk fabric, but you could use any fabric or skip it altogether.
Click title for link at Anthropologie to see their take on this collage look. Have fun with it!