Miracles do happen in the brief span of time. If you strongly believe you can score good then in the mock tests your score should be around the number you aimed for.
Revise, revise and practice questions
Attempt at least 20000 MCQs which is a key to 550+.
For 700+ by now you should know all the topics in and out. Your mock test scores should by 670+. From your name, I assume you are from Tamil Nadu, if so a piece of information, no one from the state grabbed AIR1 a score of 700+ will fetch AIR within 10 RANKS.
I can give you questions and help you revise if you are really bent upon the above score.