In general, curly hair tends to dry out more easily than straight hair, and many stylists recommend shampooing curly hair as infrequently as possible to avoid drying it out. If your hair is super fine, shampoo every other day. If you have very thick curly hair, shampoo a few times each week.
On days when you don't wash your hair, you can rinse it with water and condition it. Some stylists recommend conditioning curly hair twice a shower. When conditioning your hair, start at about an inch away from your scalp and work the condition down into the tips of your hair. You can also use leave-in conditioner to lock in moisture, which prevents frizz.