Personal podiatry care is especially important during the winter, when cold and dryness can cause skin to crack. Moisturize with foot cream after your morning shower, at least twice during the day, and before you go to bed each night, You can decrease this frequency as your feet heal.
If you notice cracks in your feet that go below the upper layers of skin, go to your podiatry clinic for treatment -- especially if your feet start to bleed. While it may not be a terrible emergency, a situation like this is definitely an infection waiting to happen.