Naturalization is the process by which foreign citizens may gain their US Citizenship. You must meet the eligibility requirements for citizenship prior to applying for naturalization. You can apply for citizenship as a green card holder or through parentage. The documentation required to apply for citizenship can be obtained through the U.S. Citizenship and Immigration Services website.
Navigate to the U.S. Citizenship and Immigration Services website and click "Apply for Citizenship (Form N-400)." Print and complete this document as a part of your citizenship process.
Copy both sides of your Permanent Resident Card, also known as your Alien Registration Card or your Green Card.
Obtain certified copies of any documents you will be using to show proof of citizenship, including a marriage license or birth certificate.