You can use various scrubs for removing dead skin. Some are easily available into the market. If you want to prepare it at home then an interesting tip is the usage of lemon juice, rose water, salt & glycerin (take all items in equal quantity & mix with each other). Now apply this mixture on the top & bottom your feet. You can also mix all these elements into lukewarm water for soaking your feet in this water. You can use pumice stone but gently from removing dead skin after soaking feet. Then wash your feet. Repeat this almost twice in a week & after some weeks you will notice that feet are becoming soft & cracks are healing.