Is there a way to turn an old wool sweater into felt slippers?

I have been reading a tiny bit about knitting and felting.

And I'm wondering .... If I have an old wool sweater, is there a way to turn it into a nice pair of felt slippers?

Does it have to be 100% wool? I have an old sweater in kinda lime green -- DD loves the color. I was going to rip it up for sock yarn, but the yarn is too thin and fragile to rip.

Is there a way to turn it into slippers?

BTW, this particular sweater is 80% wool, 20% nylon.