If you are looking for coaching classes than please do not forget these things.
must research before join.
take trial classes its very important because to trial classes you will know how the teacher teach in this center.
see who is the professor who will teach you and ask to previous student about them.
cheek the time that is according to your comfort or not.
choose the best nearest your place because you cant get good after long travel.
do not forget these things and best of luck.