Your score right now doesn't matter. What matters is your strengths and weaknesses, as identified on this test - use those to determine what to study and how to study it.
It sounds like you're taking a test every third day? If so, absolutely do not do that. At this point, you shouldn't be taking a test more than about once every 3 weeks. Taking tests is not how you get better (well, you get a little better that way, but not a lot). Taking tests is how you determine what progress you've made since your last test and what priorities you need to set going forward (based on your strengths and weaknesses). You get better by spending a lot of time studying and analyzing problems.
At this point, your time should be spent more on doing individual problems or small groups of problems (start with 5 at a time, move up to 10, 15, 20). Time yourself and hold yourself to the limit (timing is part of how you decide what to do to work through the problem!). Spend 2 to 5 times as much time reviewing each problem as you spent doing it in the first place (eg, spend 2 minutes doing the problem, spend 4 to 10 minutes reviewing problem). See my response to this post for ideas about what to analyze:
http://www.manhattangmat.com/forums/urgent-is-it-the-right-time-to-take-mgmat-cats-t6856.htmlYou also need to identify sources that teach you the material you need to know for the test (quant and grammar rules, techniques for all of the different question types, timing strategies, etc.). These can be books, online materials, a class, whatever - but something that actually teaches you what you need to know for the test. It will be a lot less efficient if you try to develop these lessons yourself from the questions and the explanations in OG.
Also, don't study for more than 2 hours at a stretch. Your brain can absorb only so much info at a time. If you try to go beyond what your brain can absorb (and for most people, that's about 2 hours max), then you'll end up not remembering / retaining the info well enough and you'll just have to go study it all over again.
For your tests, you'll obviously have to go a lot longer, but you're not trying to absorb / retain for future all the info you see over the entire length of the test. You're just focusing on answering the one problem in front of you right now.
Good luck - let us know how it goes!