Complete Form W-4 so that your employer can withhold the correct federal income tax from your pay. Give Form W-4 to your employer.First, you'll fill out your personal information including your name, address, social security number, and tax filing status. A state W-4 Form is a tax document that serves as a guide for employers to withhold a specific amount on each paycheck to go towards state taxes. Learn about income tax withholding and estimated tax payments. The Child Support Program automatically sends income withholding for support notices to a parent's employer when the employer is known. This form has complete instructions on filling out the form as will as a worksheet to help determine how much tax to withhold.