Generally, universities offering LL.M. course conduct an Entrance Test for admission to the program. One must have 55% in LLB. The application forms for this course are available in the month of April-May every year.
The entrance test paper contains around 150 questions which can be both objective and subjective in nature. The duration of the exam is 2 hours which includes negative marking for objective type questions. The marks deducted are usually 1/4th of the marks allocated to the question.
The marking scheme is not fixed for all the universities, it may vary accordingly. The long essay type generally contains 4 questions with 25 marks each. The syllabus for LL.M. entrance exam generally covers the following topic.
Jurisprudence
Constitutional Law
Legal Awareness
Current Affairs
Legal Aptitude
You can consider below-written options for doing LLM:
National Law University, Jodhpur, ILS LAW COLLEGE - PUNE, National Law School of India University ,Bangalore, Gujarat National Law University,School of Law- LOVELY PROFESSIONAL UNIVERSITY - JALANDHAR, THE WEST BENGAL NATIONAL UNIVERSITY OF JURIDICAL SCIENCES -KOLKATA, THE NATIONAL LAW INSTITUTE UNIVERSITY - BHOPAL, FACULTY OF LAW, BANARAS HINDU UNIVERSITY, VARANASI, FACULTY OF LAW-UNIVERSITY OF DELHI, NEW DELHI, NATIONAL LAW UNIVERSITY - NEW DELHI, MS Ramaiah College of Law- Bangalore, Christ University-Bangalore, NALSAR University of Law, Hyderabad,

Hey Abhishek.

The eligibility criteria for admission in various different law colleges is different from each. For admission through CLAT PG in NLUs the eligiblity criteria is a minimum aggregate of 55% marks in the UG Law degree. 

In many other colleges the eligiblity requirement is a minimum aggregate of 50% in the UG law degree.

Best of luck!