How can I become an MBA topper?

Dear Mufti Niyaz, Complete your graduation first. Then, simultaneously, prepare forCAT/MAT etc. examinations to get a top score. You can join IIMs and other top management business schools. If you join IIMA, you will become a topper. All the best.

Simply by dedication towards a purpose and nothing more is needed actually. But if you are asking for suggestions regarding study pattern and extra-curricular then fund your balance between the two. A balanced average is better than a boring book-worm.