Inconsistent performance how to attack GMAT?

[tania77]

Hi

I am very disappointed with my score in the mock test, as my performance has been fluctuating.
I was initially happy as I moved from a score of 360 to 580 and thought would score in 600's in my 4th Manhattan GMAT test but landed up scoring less than my previous test.
I am losing hope a bit. Please guide me in this regard. Every time I attempt the test I have been focusing to get first 10-15 questions right in both verbal and quants.Is my approach wrong?

Find below my scores from Manhattan GMAT:

Test Score Quant Verbal
MGMAT1 360 29 4
MGMAT2 520 43 19
MGMAT3 580 44 26
MGMAT4 440 33 19

Following is my current study plan:
Studying for 2-3 hours during weekdays and about 5-6 during weekends.
I have been taking timed test from the following site to improve my reading comprehension&SC sections.
Free GMAT Verbal Tests

Books Studied
Covered Manhattan, Kaplan, power Prep and OG books.

Exam Date
I have booked my exam dates on 30th of July. I am targeting a score of 650 + in my first attempt, many of my friends recommend to take GMAT twice, so I assume I will also give it a second shot and target for a score of 750+.

Help Needed:
Can anyone please help me with a better study plan for the next 30 days that would help me to improve my score in quant’s and verbal?
Please also provide me tips to have a consistent performance

I am positive I should be able to scale up my score to 650+,But I juz need some guidance and help at this point of time.

Regards
Tania