Not tried this myself but curious to hear if anyone has and if it works? May have a go later.
1/4 cup of Listerine (blue one but others are good to use as well)
1/4 of a cup vinegar
1/2 cup warm water
Soak for 10 mins. When you take them out dead skin will practically wipe off. (Or so they say....)
Anyone tried it? Not so keen on the vinegar to be honest.