You file a petition with the family court that has jurisdiction over your case, and convince the court that such a move is in the best interest of the child - which includes a plan regarding how you plan to continue to encourage and facilitate the bond between father and child. If you're going to attempt to create distance between dad and his child, you need to be prepared for dad to challenge that move, and, for dad to ask for you to be VERY generous in terms of you bearing the brunt of travel expenses for him to exercise his visitation, as well as generous chunks of visitation time during holidays and summer breaks, phone contact, skype, etc.