Students from any academic background may apply to the M.A. in Linguistics or the Graduate TESOL Certificate. You do not have to have previously studied Linguistics, but students transitioning from other fields may need to complete prerequisite coursework.
There is a two-step process for applying to the linguistics graduate program.
Apply to the linguistics department, by sending a personal statement and an academic writing sample
Your personal statement should address: (a) your interest in and knowledge of linguistics as a field of study, (b) your educational background, (c) your experience with diverse languages and cultures, (d) your professional, research, and/or teaching experience, and (e) your professional goals. If your GPA is below the department's minimum requirement (see details below), or your educational record has other issues you would like to explain, please address this as well.

Your writing sample should be an academic paper written by you in English. It does not have to be on linguistics.
The general university minimum requirements include:

Completion of a four-year college course of study leading to an acceptable baccalaureate degree from an accredited institution.
Good standing at the last college or university attended.
An English language demonstration for applicants who do not have a bachelor's or master's degree from a U.S. accredited institution. Please consult our webpage for potential MA students that provides both more details about the benefits, opportunities and resources available to students who pursue an MA at CSULB and additional information and links for international students about deferred admission for students who need to enroll in the American Language Institute to perfect their English as well as options for N200 students to be evaluated by the department in lieu of standardized testing.
The Linguistics department additionally requires:

A GPA of at least 3.0 in the last 60 semester units or 90 quarter units attempted, excluding lower division and extension coursework taken after the degree. Exceptions will be considered on a case-by-case basis.
Have earned a grade point average of at least 2.5 on the last degree completed by the candidate or have attained a grade point average of at least 2.5 (A=4.0) in the last 60 semester (90 quarter) units attempted.

IELTS - 6.5
TOEFL Internet-based (iBT) - 80
TOEFL Paper-based - 550