Just like the original agreement, the amending agreement must be signed by each party in the presence of a witness, who watches the party sign the agreement and then signs the agreement themselves. The same person can be the witness for both parties.

A well-written family law agreement will usually provide a way for the parties to resolve disputes arising from the agreement if they can't resolve a dispute by negotiating a resolution on their own. Sometimes an agreement requires that the parties go to court to resolve disputes about the agreement; most often, an agreement will require the parties to try to resolve their dispute out of court through mediation or arbitration.