Hi harvardforsure,
To start, a 650 is a fantastic initial CAT score (the average score on the Official GMAT hovers around 550 most years). Statistically-speaking, raising a 650 to the point that you can consistently score 730+ would likely require at least another 1.5 - 2 months of consistent, guided study. Thankfully, the GMAT is a consistent, predictable Exam, so you CAN train to score at a higher level.
Before I can offer you the specific advice that you’re looking for, it would help if you could provide a bit more information on how you've been studying and your goals:
1) What study materials do you currently have access to?
2) When are you planning to apply to Business School and what Schools are you planning to apply to?
3) Going forward, how many hours do you think you can consistently study each week?
GMAT assassins aren't born, they're made,
Rich