Hi Abhinav,
Here is my advice based on my strategies.
Quant -
MGMAT CAT gives you a detailed report of the areas you are weak in. Look at the reports and take a few days 2-3 to brush up those concepts using your
MGMAT guides and retry all the questions related to those topics from the OG guides.
CR - I would strongly advice you to read "CR Bible" - both CR concepts and questions in this book are excellent. Since you are short on time, you can read only those topics that you are lagging behind in.
RC - Best way to perfect this is practice!! You have to read efficiently - take ~2 mins to read a short passage and ~3 mins for a long passage - make sure you understand what each paragraph is about and how it is linked to other paragraphs - Always cross verify your answers to specific questions with the passage. Try to solve SC questions quickly so that you have more time left for CR and RC, as you have more to read on these questions.
Try to take two
MGMAT tests a week and keep studying and practicing those topics that you do not do well on. Also, make sure that you go through the explanations of incorrect questions and make notes wherever you encounter a new/forgotten concept. you can refer these notes on a regular basis until your test date.
You may think about purchasing the additional question pack ($25) from GMAT in case you want to practice more with actual GMAT questions.
Best of Luck for your exam!!