While what to feed baby may be a no-brainer, how much to feed baby is not such a simple matter. Generally, newborns likely will polish off 1 to 3 ounces per feeding, and will graduate to 2 to 4 ounces as they get a little older, says Unger. By 4 months baby may suck down 6 to 8 ounces per feeding, says Collins. Keep in mind, however, that every baby is different and while you want to be careful not to underfeed baby, overfeeding baby shouldn't be a concern, unless baby is throwing up, says Unger. "Weight gain in the first four months of life is not related to obesity later on," she says. Therefore, it's probably safest to put a little more in baby's bottle than you think he will drink. That way, when he's ready to graduate to bigger feedings he'll have plenty to eat. Still, be alert for signs that baby has had enough: if he turns his head away or stops drinking, he may be trying to tell you something.

The bottom line in deciding how much to feed baby and how often he needs to eat: steer clear of rigid guidelines and instead look to your baby for clues. "I think parenting books are wonderful and great to keep you informed about what is happening to other babies, but they don't apply to one baby," says Collins. So read the books. Then put them away and let baby be your guide.

Helpful hint: Don't get into the habit of letting baby fall asleep with a bottle in his mouth — milk pools in the mouth and promotes tooth decay. Even if your little one is still toothless, you'll be starting a habit that is hard to break later.

4 to 6 Months
By 4 months you're probably more than ready for something new. The good news is that baby is too: It's time to start solid food. Or, more accurately, mushy food — whether it's from a box, jar or your own blender, at this age baby is only ready for smoothly puréed meals.

Of course, as with any guidelines about feeding baby, keep in mind that the timing for solid food varies by baby, too. "By 3 or 4 months baby will probably be ready to take a spoon," says Collins. Even so, for the first few feedings — and maybe longer — don't be surprised if much of the food ends up on rather than in baby. Baby should get the hang of this new skill pretty quickly, however, says Collins. If baby pushes every bite out with his tongue or turns his head away every time, he's probably not ready. "If he doesn't get the gist, I say put the spoon away and try again in two weeks," says Collins.