Passport application, naturalization certificate, drivers license, check or debit/credit card to pay the fees, Very important not to sign the passport application before hand! Only in front of USPS employee. They will take your Original naturalization certificate with the application but it will come back to you by mail at some point. 1 passport style photo, some USPS facilities don’t offer this service, make sure yours does if not got to CVS, Walgreens or the equivalent in your area to have your passport style picture taken before you show up at USPS facility. Then the waiting game starts.