I've come to love wet felting--which is the magic of whipping up lovely wearable art out of unlikely components. It is true alchemy.
I also like wet felting because it is an art rather than a science. The results are always a mystery to the artist. With practice, you can control your results better, but part of the fun is precisely its unpredictability.
The felted neck wrap in this instructable is made out of cheap mesh fabric (from a post-Halloween sale) and various loose fibers including merino wool, bamboo and silk. I didn't measure anything in the making of this neck wrap, but here are the approximate materials needed:
A piece of mesh fabric about 8" x 48"
Merino wool roving (less than an ounce)
Bamboo fibers for use in felting (a handful)
Silk yarn (about 60 inches)
Step 1: Laying out the Fibers
Lay the mesh over a piece of bubble wrap with the bubble side away from the mesh (although I've done it the other way also).
Spread several layers of natural fibers onto the mesh in alternating directions. For this felted wrap I put two layers of a variegated red merino wool; a couple layers of gray and white merino wool; a few shimmery bamboo fibers in greens and yellows placed here and there; and a length of teal silk yarn looped over the other fibers. To secure the silk yarn, I added an almost imperceptible layer of white merino wool on top of it.