Mrrinali wrote:Could you also suggest me a strategy to prepare for Maths (whilst I cover the English as per the BTG Online Prep) to sharpen my learning and improve my score? Thanks

Hi Mrrinali.
To improve your GMAT quant skills, go through your practice test and and practice questions to determine what types of questions you are least comfortable with, which ones you don't get correct consistently, and which ones you take the longest to answer. Basically, you are seeking to determine which types of quant questions you don't want to see when you take the GMAT, as least as things stand.
Once you have found some types that fit the above description, focus on those types one at a time. For instance, if you find that you are not comfortable with overlapping sets questions, learn all about how to answer overlapping sets questions, and then answer overlapping sets questions until you go from not wanting to see them on the test to being excited to see them on the test. Then, go to the next category. You can be sure that, if you get better at answering questions of types that you are not comfortable with now, your quant score will increase, and your stress level will decrease.
By the way, the 68th percentile in quant is a decent score that is likely high enough to get you into any school. At the same time, since you retook a test that you had already taken once, your score may be slightly inflated if you saw questions that you had seen previously, even if you didn't completely remember those questions. If you don't mind spending the money, probably you should purchase one or both of the Exam Packs from mba.com.
https://www.mba.com/us/store/store-cata ... CAT2680001 Each pack contains another two practice tests. If you do so, you will be using fresh practice tests, and scores on those tests will not be inflated.