Corporate Lawyer

There is no sure shot formula to become any kind of lawyer in India or otherwise.
However, one can take the following steps that may work in favour of establishing your career as a lawyer in the field of Corporate law.
When you get admission in law school if given a choice, option for BBA LLB to get a brief idea of companies and their management. During your time at law school, make sure you focus on Contract Law and Companies Law, as they form the basis of corporate law, to get a theoretical understanding of what the field is all about and what all it will encompass.
Try and choose internships and apprenticeships under a reputed firm dealing in Corporate law in order to build a good CV and also to gain a practical knowledge of the field that you are interested in.
After law school, try and focus your energies on getting a job with any firm reputed for their corporate law.
You could enroll in a diploma/certificate course in Business/Corporate law to boost your CV.
An LLM in Corporate Law from a reputed international institution may be a good idea, but LLM, in terms of job prospects, does not really boost your chances.