Whats the best thing to do when your bottom of the heel hurts and the skin gets cracked?

Moisturize the crack: The heel pain may be related to the fissure or may not be and this has to be figured out.

Lotion!: Use a thick lotion, apply daily or twice daily to soften the skin. See a dermatologist or podiatrist for more aggressive treatment options. Don't go barefoot or wear open-backed shoes, and don't soak your feet--this tends to chap them and dry them out even more!