Diaper rash generally happens when the skin covered by the diaper is wet or soiled for too long. The easiest way to prevent it is to change your baby's diaper often. Ideally, a diaper should be changed every time it becomes soiled. That way, any wetness won't rub up against your baby's skin and irritate it.
If you're having a hard time discerning when your baby's diaper is wet or soiled, check it every couple of hours during the day. Newborns will need changing more often than older babies. All caretakers, including baby-sitters and day care workers, should be diligent about checking a baby for wetness and changing the diaper as soon as it's dirty. At night you'll also want to check the diaper to make sure he doesn't spend several hours sleeping with a wet or soiled diaper next to his skin.
When putting on a baby's diaper, be sure that it's not too tight. Sure, you don't want anything to leak out, but if a diaper is too tight, air can't flow through it, which creates the perfect environment for moisture getting trapped and irritating the skin.
Cleanliness is also important, and next up, we'll look at how to keep your baby's bottom clean.