A bunch of other stuff has been covered, so I'll just talk about communication.

Talking to teachers, preschool especially; kids are coming in with worse and worse communication skills.

The #1 bit of advice to have a kid that speaks well; talk to your baby, regularly,like about everything you are doing with/to them. Before they can speak they are learning words; phrasing and cadence.

I read somewhere years ago, before our first baby; that, babies learn new words when they are spoken to directly, they cement how to use those words when they hear their parents use words with others.

Edit: "baby speak" is not required....speak normally; singing however is great they love it.