You need to:
(1) Have a bachelor's degree in the same or an allied discipline in an accredited university
(2) If you earned your bachelor's degree from a foreign institution, you may need to take the TOEFL, TSE tests.
(3) You may need to get a doctoral candidacy examination
(4) You may need to get a master's degree
(5) You may need to get a minimum number of credits in certain subjects
(6) You may need to pick a topic and a mentor for your doctoral research
(7) You may need to publish a minimum number of papers
(8) You may need to present and defend your research findings before an evaluation committee.