CitizenPath has created a sample cover letter to help you file Form N-400, Application for Naturalization.
Use this sample cover letter as a guide. Do not submit this letter without updating it to fit your specific situation. It is not mandatory to submit a cover letter when you file Form N-400, but a cover letter can help to clarify the purpose of the application and why your application may be unique.
After you have prepared your Form N-400, Application for Naturalization, you can refer to the custom filing instructions from CitizenPath for the USCIS mailing address, filing fee and additional documents to submit.