Clean feet and apply an antibiotic ointment or cream twice a day to begin the healing processs. Keep feet clean and moisturized daily to help prevent further problems.
Heal them first. Slather on triple antibiotic, put on clean socks and sleep in them. Once healed, do the same with petroleum jelly. Soft feet in just days!
The reason your heels are cracking is they're really dry. What you need to do is keep lotion on them during the dry season. This will stop the cracking.