The sole is white fleece, and I also used fleece to line the toe area. I originally lined the heel with fleece, but since you fold it down and sew to encase the elastic, it was too bulky and the elastic wasn’t allowed to do it’s job. I made a different heel with white cotton as the lining instead.
I got the pattern from Stardustshoes’ blog (Click here to download the pdf instructions). They go really quickly and are super cute!