The first step in this process, is filling out the paperwork properly. Basic Steps to filing for custody in Cook County, IL. Preliminary Matters.Use this form to ask the judge to give you parental responsibilities for a child. This includes parenting time (visitation) and decision-making power (custody). Fill out and sign or esign your forms. Make four copies of each form. Download and complete Motion and Notice forms from the Illinois Office of the Courts. If no agreement can be reached after completing the Resolving Disagreements process, file a petition to modify the parenting time schedule with the court. e. If no agreement can be reached after completing the Resolving Disagreements process, file a petition to modify the parenting time schedule with the court. e. The form may be attached to the most recent care plan.