The bulk of your time in the last month should be dedicated to revising what you have learnt.
It is better to revise what you already know rather than learning new concepts.
Split your day for revision of each subject. Spend 2-3 hours on each subject
Analyzing your performance in a mock is as important as giving a mock. Pay attention to the errors you make.
Make sure you go through the previous year papers of atleast the last 5 years. You will get a fair idea of the variety and difficulty of the questions asked.