Cleaning toes on a casted foot?

I broke my ankle 4 weeks ago tomorrow, so I have a cast that goes almost all the way up to my knee. Yesterday I found out I have a disgusting amount of dead skin on the underside of all of my toes, does anyone have any advice on how to clean it off? I've been picking at it with my fingers but it's hard to get my foot that close with my cast to see what I'm doing and I can't get my cast wet either 😞