You will need to complete and serve all of the same forms you originally filed, indicating that the new filing is amended. This Roadmap is a guide to aid in completing the paperwork for a divorce.This guide is intended to be a roadmap that will give you a preview of expectations and mistakes to avoid. Here are 10 basic steps to the divorce process. Learn how to modify child custody in California, including the requirements, process, and forms necessary, and where to find cheap, professional help. If your divorce has been finalized, but your circumstances have changed, you have the right to seek a modification of certain court orders. Complete the necessary forms from the list below. Unsure which forms you need? You can file a petition for child custody in your county's Superior Court. If you are divorcing, the petition will be included in your divorce papers.