Keep track of questions you got right and wrong (with your
error log). Look at the questions you got right and find out what the test was asking for (i.e. Geometry? Work or Rate problems?)
Do the same for the questions you got wrong. I have a notebook of all the questions I got wrong during my preparation. I wrote the question in black ink and the solution in red ink and then identified what I missed the first time around. For example, I used to miss word problems that asked for a percentage of a percentage. Now, I've recognized this type of problem and know what they're looking for.
You should get to the point where you see a questions and know how to approach it right away. For example, Distance or Work problems. If you've read
MGMAT, you know to draw a chart with Rate, Time, Distance (or Work). Practice the easy problems first so you get the basics down then move on to more advanced questions.
MGMAT give you problems in this format and I highly recommend you get the math series.
Some of the questions may just be tricky but if you've done enough problems, you can recognize the "easy" way. For example: what is (0.99999)*(1.00001)? Impossible, right? But if you do (1-0.00001)(1+0.00001) it's much easier b/c you can then follow the (x-y)(x+y) rule where the end solutions is x^2 - y^2. In this case it would be (1)^2 - (0.00001)^2.
For Verbal, I'd say focus on SC and use
MGMAT as your guide. Once you learn to recognize the question types, practice, practice, practice. You should be able to identify the 3/2 method (eliminate 3 or 2 of the choices right away) and then continue the process of elimination (POE) to find the right answer. THis takes practice and the GMAT club forum is a great place to practice.
For CR, try writing out a 5-8 word summary of the given information (like a math solution). If it's an assumption question, find the missing piece of info that gives you enough to reach your conclusion. The key is to look for answers that don't bring in any outside information than what you were originally given. Again, practice and it should start to become clear.
For RC, I found this was a big killer for me. I eventually learned to read just a few sentences out of the passage to understand the author's intent and what the body paragraphs presented (evidence, counter-evidence, etc.).
Work on problems first, understand how GMAT is trying to trick you and double check your answers for silly mistakes (huge penalty for easy questions).
Also, I think I mentioned this before, timing plays a big role. If you don't finish the section in time, you get a big penalty. If you can't pace yourself, at least guess on the last few questions--never leave em blank.
Hope that helps.
-JJ