Now that Paternity has been established, how to I go about adding the father to my son's birth certificatr?

Contact the clerk of the county.

Here in Florida, if you contact the Office of Vital Statistics they will advise you of the documents you will need to submit in order to add the father to the birth certificate. It depends on how paternity was established, if you have the results of a DNA test through your local child support office, you will need that order signed by a judge, certified and mailed to the office of vital statistics along with your i.d. and whatever fee they charge to do this. Usually your local child support office will do this for free. If a father admitted paternity in open court (family court), you will need the order signed by a judge, certified and sent to the office of vital statistics. If you and the father signed a DH432 form you will need to send the original document, signed by a notary public to the office of vital statistics and their fee and they will update the child's birth certificate. If you contact your local child support office, they should be able to inform you how to go about this or provide you with the phone nbr to your local office of vital statistics.