At my weekly knitting group we talked about different ways to stop knitted slippers from being so... well, slippery. One of the members asked why you couldn't stitch rubberized rug nonskid to the bottom? So I thought I'd give it a try.
I traced the outline of my foot onto paper to make a pattern. Then I cut a left and a right out of the nonskid.
I hand stitched them to the bottoms with two strands of sewing thread and buried the knots.
They're great! And it might make the slipper bottoms wear a little longer. During our Christmas visit with the kids, I did the same for Evan's slippers. He's so effusive, he said, "Grandma! This is AMAZING! Thank you!!" No more slipping on the hardwood floors.