One thing to tell, never spend more than 4 minutes on a problem.
I have been preparing for the Gmat for a month. My major preparation was verbal. I only did the quantitative preparation at Gmatclub and the Kaplan CD. Also looked a little bit at OG for the quantitative part.
To be honest, the test was similar to the OG problems. Nothing fancy. My major mistake I did was staying aroung 15 minutes on a math problem which was the 10th one I think. As I was confident that I can solve each problem in test,this problem shook me.The sad part is that I didn't quite understand the problem. This affected my overall focus on quantitaive. As for verbal, I was glad with my performance.
As a whole a score of 640 is not bad, bearing in mind this is my first attempt and only a month training.
just to put all the tests I took before Gmat.
powerprep PP1 600 (50,22) before practicing anything.
Kaplan CAT1 560 ( Q50, 23)
CAT2 560 (Q50,23)
Wish all of you the best of luck on your test.