Just to add my 2 cents. It is clear that you need to work on both quant and verbal. Also, you need to divide the 200 point jump in 3 jumps - say from 540 to 620, 620 to 670, and the last being 670 to 700+. Note, these are mock test scores and not actual GMAT attempts. Even though you stated that you have completed OG12 and some other resources, you scores indicate that you have not understood the fundamentals or mastered the concepts. Here are a few questions that you should ask yourself:
1. What is your strength = Quant of Verbal? Make sure you capitalize on your strength first.
2. How much time can you spend per day - have a realistic estimate. Note this time is high quality time.
Overall, you are looking at 200+ hrs of effort to attain your desired improvement. Hence, either change your goal or schedule your next attempt accordingly.
Study Plan:I conduct a 2 hr session on GMAT strategy and study plan. Below is a recording of one such session. It also includes a study plan and a few other things.
https://meet25754052.adobeconnect.com/p4sb588p1sy/Regards,
Rajat Sadana