Your doctor might give you a prescription for a special cream to use on your baby's rash. Talcum powder and cornstarch aren't recommended. Talcum powder can get in your baby's lungs. Cornstarch may make a yeast infection worse. The choice is up to you.
Some research suggests that because disposable diapers are more absorbent they keep babies drier.
If you use cloth diapers and wash them at home, boil them for 15 minutes on the stove after washing them to kill germs and remove soap that could irritate your baby's skin. But remember that the most important thing about diapers is to change them often.