I don't do anything to the selvage edges....they are already finished. I put purchased fringe on the raw edges.

Crochet fringe!
I'm currently making a throw from an upholstery remnant.
1)Pre-wash the remnant to soften it. You can line it with fleece if you want but mine looked good on both sides.
2)square the raw edges
3)leave the selvage as is
4)hem the raw edges.
5)blanket stitch along the hemmed edge
6)crochet into the blanket stitch to make the fringe. I used a fringe pattern that I found on a free crochet patterns web site.
It's very nice. I could have used purchased fringe but I had the perfect yarn in my stash already.

I've also finished throws by sewing a contrasting piece of fleece maybe 6 inches wide onto the raw edges and fringing it.

I've made 20 or 30 of these and never done anything but knot the fringes. They wash up nicely and hold together so there is no need to finish the edges. Fleece doesn't ravel.