To enroll, please complete an application and send it to Tarrant County Child Support Services. Clipboard and Pencil.These forms allow parents, families, and employers to provide the Child Support Division with additional information so we can better serve you. Wage withholding lets you make your child support payments through your regular paycheck. This calculator provides an estimate for a single source of income. Fill out the required IWO form. This guide includes forms and instructions for a letter and affidavit to request that the court register an outofstate custody order in Texas. Complete Form W-4 so that your employer can withhold the correct federal income tax from your pay.