Calculate Your Withholding: Determine the amount of federal income tax to withhold from your pay by using the IRS withholding calculator or the tax tables provided in IRS Publication 15. 2. Complete Form W-4: Enter your withholding information on Form W-4, Employee’s Withholding Allowance Certificate. 3. Send Form W-4 to Your Employer: Submit the completed form to your employer. 4. Track Your Withholding: Your employer must keep a copy of your Form W-4 on file and use it to calculate the amount of taxes to withhold from your paycheck. Your employer should provide you with a statement (usually on your paycheck stub) showing the amount of federal income tax withheld from each paycheck.