It's important to give kids food every few hours for the first few months. When they are hungry, they'll let you know. At some point (4 months? not sure what the experts say) you can start trying to get them to sleep at night.

When you finally get them sleeping through the night, it's important for them to go to sleep and wake up at the same time every day, including weekends. It puts a huge dent in your social life, but it results in happy, pleasant kids.

If you provide an environment where your kids are on a regular sleep schedule every single night, that's way more than half the battle.

More than anything else, mentally prepare for world where everything you do is controlled by a little baby, and their needs.