These forms and instructions are available in the General Clerk's Office, Room 108, in the Nassau County. Petition for (Custody) (Visitation).Find and download various legal forms, brochures, and self-help kits. If a form does not open, right-click the link to save it to your computer. First, download and complete the request form. The Judicial Branch has refreshed the Official Court Webforms page. Forms are divided into categories. You must file the Affidavit in cases involving the care, custody, visitation, or change of name of a child. This program guides you step-by-step through court forms on any computer or mobile device. Answer a few simple questions and receive a completed PDF document.