That's a good starting point! In general, you'll need to figure out what your best "opportunity weaknesses" are so that you can selectively try to improve them. I'll describe the process below. If you're taking a class, it's a good idea to talk with your teacher about your analysis. If not, feel free to come back and post your analysis here and we'll discuss.
First, read these two articles:
http://tinyurl.com/executivereasoninghttp://tinyurl.com/2ndlevelofgmatThink about how what you've been doing does and doesn't match up with that and how you may need to change your general study approach accordingly.
Then, use the below to analyze your most recent MPrep CATs (this should take you a minimum of 1 hour):
http://tinyurl.com/analyzeyourcatsBased on all of that, figure out your strengths and weaknesses as well as any ideas you have for what you think you should do. As I mentioned, think about what I call your "opportunity" weaknesses—not the things that are the worst-worst-worst for you, but the things that are a weakness in some way but also an opportunity. (Examples: Careless mistakes. You got it right but took a little longer than you'd like. You got it wrong but the explanation makes complete sense to you.)
Then talk to your teacher or come back here and tell us; we'll tell you whether we agree and advise you further. (Note: do share an analysis with us, not just the raw data. Your analysis should include a discussion of your buckets—you'll understand what that means when you read the last article. Part of getting better is developing your ability to analyze your result—figure out what they mean and what you think you should do about them!)