Get in shape. Babies keep you moving, and it's more fun if you are in shape.
Buy and read these books:
"What to Expect When You're Expecting",
"What to Expect the First Year".
and "Super Baby Food", (You should be making all of the babies food for them, no need for jar food).
Don't bother to buy clothes for the baby. Family and friends will provide plenty, and the baby will grow out of half of them before you even have a chance to put them on it.
Get plenty of diapers, plenty of wipes, and plenty of burpy cloths. You'll go through those faster than you can dream is possible.
Start reading to the baby in the womb, and keep it up once they are born.
Leave the damn TV off for the first year at least. Later, when they do watch, make sure you are with them and talking to them about what they are watching. Interact, don't just let them stare at it passively. Many studies link this to ADD later on in life.
See plenty of movies now, you won't be going to a movie theater any time soon.
Relax and have a great time! They require more attention than you can imagine, but they are also the most fun you can have in life.
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