The name change petition can be filed in the County Court or Supreme Court of the county where you live. The forms for changing a name or sex designation in the Supreme Court or New York City Civil Court are included in the chart below.1. Provide an Affidavit: Obtain an affidavit from a notary stating the spelling variation and the relationship between you and your father. Need a name change affidavit? Simplify the process with NewlyNamed's comprehensive kit. The child's surname can be changed with this same form. Intheblanks form required for any matter originating and electronically filed in Supreme or Surrogate's Courts in Richmond County. This page explains the procedure for obtaining a Marriage License from the Office of the New York City Clerk