Cases involving child custody can be filed two ways: jointly or separately. If you and the other parent agree on everything, you can file a joint petition.Print the state and county where the form is notarized in the spaces provided. Sign your name in front of a notary. Forms Packet: Request to Establish Custody and Parenting Time. Order On Motion for Sibling Placement or Contact. The petitioner does not always have to fill out and file the petition on his own. The person who prepares the actual petition may vary from county to county. The purpose of the DR calendar. 6. Read the instructions and fill out the form.