The U.S. Citizenship and Immigration Services requires that all foreign language documents (birth certificates, diplomas, etc.) be submitted together with certified translations into English. The translator must certify that he/she is competent to translate and that the translation is accurate.
You may hire a professional translator, although this is not required. These translators have their own standard certification language.
The document may be translated by yourself or by someone you know, but you may not certify your own translation. Have someone who is able to understand both the original document and the translation make the certification. The document translation should be laid out on the page exactly as the original document is laid out. The certification should be made either at the bottom of the English version of the document or on a separate page, attached to the English version. The certification format should include the certifier's name, signature, title (if applicable), address, and date of signature.
The suggested format is:
I ___________________ (type name), certify that I am fluent (conversant) in English and ___________________ languages, and that the above/attached document is a true and accurate translation of the above attached document entitled ______________________________________
(It is helpful for the certification to include some detail regarding the certifier's background in both languages.)
For example:
I am qualified to translate this document because (Chinese) is my native language and English is my second, acquired language. I grew up in China but have lived in the United States since 1991, and am currently an Instructor in Chinese at the Massachusetts Institute of Technology.
Signature__________________________
Date______________________________
Typed Name, title____________________
Address____________________________