See if you can go beyond the practice test scores to identify the areas where you most frequently get tripped up.
For example, I realized that my key areas of weakness were on data sufficiency in general, geometry, propreties of exponents, combinatrics and probability, rate/work problems, and sentence correction (especially with collective verb subjects). So I spent a lot of time reviewing material on each section - theory and practice.
I also realized my main pitfall in the quant section was timing (I kept running out) and the main reason was that I'm very slow at doing arithmetic without a calculator. So I studied some tips to quickly add, subtract, multiply and divide numbers and learned some of the main ratios and square roots by heart to simplify things. And then I timed myself doing complicated calculations without a calculator to get my speed up. It seems to have helped, because I had way more time on the last couple of practice tests I took in math, and didn't have to rush through the last few questions.
In verbal, I realized the problem was opposite; I was going through the questions too quickly, and not thinking them through enough. I did a number of practice questions extra-slowly, writing out point by point my argument for why I thought it was the answer in longhand on scratch paper before actually confirming the answer. I made the case to myself as though I was typing an explanation on this board, for example. A few times, while making the argument to myself, I realized where I was going wrong, and went back and changed the answer.
I don't know whether all of this will pay off - I'm now test date minus 2 so we'll see how it goes. But I know that identifying areas to study is probably more valuable than just doing a bunch of practice questions.