The only preparation is to put yourself on a footing to where you can be the best father you can be.
If you are employed, then do what you can to keep your job or improve on it.
If you aren't employed, then try and find a job so you can support your child.
Look for things to do to baby proof your home. If you have guns, either make sure they are in a safe, or store them outside of your home.
Love your child. Make sure that child knows that his or her father will be there when they need you.
If the situation allows it, be there for the mother. Do what you can to make her feel comfortable and secure.