The first step is to file a civil complaint in district or federal court depending on the dollar amount with pleadings or reasons of why you believe the defendant should be ordered by the court to do what you have asked it to do (I.e. pay money, etc.). At this point the defendant will have a chance to respond and a court date will be set. The Judge will hear the arguments of both or all parties, and will either find in favor of the plaintiff, or in favor of the defendant if there is a counterclaim, or dismiss the case altogether.