The most important question faced in any MBA interview is Why an MBA?
It is expected for each MBA aspirant to be logically able to answer this question. One should be very clear in his mind, why one needs an MBA, how it is possibly related to his work or how he has shown inclination towards an MBA and how will an MBA help his career growth.
So, one should analyze his profile and map it to an MBA, you should be able to convince the interview panel Why you need an MBA and the interview is half conquered.
For example, in my case, i am a Sales Engineer in an IT product firm in Bangalore, i convinced the panel of my interest in Customer dealings and my Sales related job profile and thus the need for a Marketing MBA, agreed it was easy in my case. But if your job profile is not related directly to an MBA, you can always provide such examples of some work in your college or work-place or may be some social work which stimulates interest in an MBA specialization.
Next thing is to know your career goals, this is to complement the previous point only. You should try to know what a CMO (chief marketing officer) does, if you an interested in an Marketing MBA. Know about all the roles of an Investment Banker, if you are interested in Finance-IB. Try to have a rough idea of what you want to achieve and where to do you want to be post an MBA.
Thirdly, evaluate your profile in deep, see what all are your strengths, your weaknesses, things where you have contributed to the society or impacted some one, some radical improvement you have brought about in yourself etc., be very thorough with yourself and truthful to the panel.
What you seek from an MBA college is Brand, Skills and Networking!
A popular brand can be an IIM, XL, SP Jain, Narsee Monjee, IIT etc. Skills will be imparted to you in the due course of time; faculty and infrastructure of a college have a major role to play in the same. A good batch profile will provide some great friends and an invaluable networking.
One important thing is AWARENESS, collect sufficient info on the college history and background of the college for whose interview you are appearing. Have complete info on the MBA specialization you are applying for OR are interested in, for eg. you should be thorough with what PMIR means and all it encapsulates if you are appearing for an XL PMIR/HRM interview. A know-how of specific MBA roles is essential.
Always be updated with current affairs, general knowledge etc., these are small things that can help in an MBA interview.
Be thorough with your profile and your MBA story, be truthful to the panel.
Be GRACIOUS, they need a smiling, truthful and a confident candidate; just some basic preparation and an MBA interview is not so tough, Market your positives, sell them your plain and simple MBA story and you are there :)
Keep it SIMPLE and good luck.