Both parties must possess a valid government issued picture identification that includes the full legal name and date of birth. If the form you need is not on the Judicial Council website, you will have to make your own form which follows these rules.Edit, sign, and share contra costa county marriage license form online. No need to install software, just go to DocHub, and sign up instantly and for free. View a sample Marriage License (PDF, 314KB, 1pg.). These forms must be filled out in person. Both parties must appear in person and bring valid picture identification to the County Clerk's Office to apply for a marriage license in California. How to fill out the Affidavit for Marriage Witness Sample Form?