Hi and Congratulations! On the baby and for starting to work on this at this time instead of waiting till the baby's home or you're having trouble. Good job! 
There is so much you can do to insure a smooth transition. Most of it has already been written up in articles on the Internet. Here are a couple I find particularly good. In my opinion, the one most important thing you can do is to have your dog very well obedience trained and prepared. If he hasn't taken obedience classes, get him started now and work with him till he's very responsive. Secondly, it's important that the dog sees the baby as one of the "leaders" in the house.
Preparing your dog for a life with Baby.
Introducing your New Baby to Your "Old Baby".
And don't forget NILIF.
If you google preparing dog for baby you'll find a lot of good ideas. Good luck!
LSTM (Laughing Silently to Myself)
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