Take plenty of pictures and plenty of video. They grow up fast.
After the first year, don't make the mistake of letting them sleep with you. It's hard to break them from it.
Start using alternate words when you smash your thumb with a hammer or stub your toe in the house. They remember everything they hear and repeat it at the most unexpected time......usually when the in-laws are present.
Don't put everything up. Instead teach them not to mess with stuff that they aren't suppose to mess with. This helps when going over to someones house that doesn't have kids.
Don't be too lenient as they turn 2-3 or you will be paying for it until they are 18-20
As stated earlier.... Always listen.
Congratulations. It is definetly a life changer, but for the better. The good times will out weight the bad 100 times over.
Again, Congratulations to you both.
Hedworx