First, learn to sit for at least 2 hours at a stretch
Solve every question of NCERT by hand, without looking at the solution.
Solve NCERT Exemplar (if available)
Sit through chapter wise FULLY INVIGILATED TESTS
Practice MCQ Questions (Very Important)
Practice Assertion Reason & Case Study Based Questions
Sit through FULLY INVIGILATED TESTS involving MCQs. Assertion reason & Case Study Based Questions
After Completing everything mentioned above, Sit for atleast 6 full syllabus TESTS.