Hi Guys!....I need some advice...Praetorian, et al., please find time from ur busy schedule and provide me with some of ur valuable insights.

I got a 600 in Princeton test, which i gave this morning:
Math -
Problem Solving: 70%
Data Sufficiency: 52%
Verbal -
Sentence Correction: 80%
Reading Comprehension: 15%
Critical Reasoning: 61%

NOw 600 is a bad score, but it was good for a couple of reasons:
1. after the math section, my concentration was screwed. I wanted to just end the test and get the hell out of the room. It took me 10 mins to solve the first 3 problems in the verbal section, and after that my mind was even more screwed. I solved the other problems in a haste. The last 2 RC sections i just ignore completely, blindly clicking on any random answer (that explains the 15%).
2. This is a test i gave after almost a month (!) and has been my highest score till date. While solving the verbal i seriously thought i would land up with a score in the 400 region. Relatively speaking, a 600 is good. With all the screw up i BELIEVE i can do much better than this -
I only need to spend time on data sufficiency and reading comprehension while maintaining (...or doing better) in problem solving, sectence correction and critical reasoning!

I am aiming at getting a 650+ in my next test which I intend on taking on the 18th. My actual GMAT test is scheduled on the 8th Nov, I have hardly a month left. I have taken leave from work just so that I can focus 100% on this test. I need your advice on the following:



My question is as follows...just how much practise is good practise? in other words, how and when would i know that im well prepared? My problem is inconsistency...coz if i do well in some sections in one test, i do bad in those same sections in another test, and vice-versa. I need to rectify this problem and minimize my errors.