Good question! A new baby needs to nurse at least 8-12 times in 24 hours. To breastfeed successfully, it's important to nurse whenever the baby is hungry. Usually this works out to a feeding every 1 ½ - 3 hours (timed from the start of one feed to the start of the next). Some babies like to bunch several feedings into only a few hours, and then may take a longer nap. It sounds like a lot but remember that this is only at the beginning. Your baby will begin to take more at each feeding and will start to go longer between feedings in a couple of months.
Watch for feeding cues, even if he is asleep. Try to feed him before he starts crying. Watch and listen for:
Leave the baby on the first breast until he will no longer suck and swallow when you massage the breast. Then (after a nice burp!) nurse on the other side if he is willing. It's fine to nurse on just one breast per feeding if your baby is satisfied. Let the baby decide when the feeding is over - he will let go on his own and probably fall asleep.