You'll hate me for this, but I didn't prepare at all and got a 30. I had initially decided that was just a trial run, but since my score was high enough to get in anywhere I wanted to go, I never took it again.
Advice:
I have is if you get stuck on a question and you've spent over 2 minutes on it and still have no clue, just pick your best guess for an answer and move on. Go back to it if you have time when you've completed the section. It's much better to do this than spend so long on the question that you're rushed through the last few questions and possibly mess up on the ones that you otherwise would do well on.
For the writing portion, give real examples to back up your opinion/claim. If you know something happened but you don't remember the exact date, provide a date that seems reasonable (e.g. if you know something happened in the '70's say "1976"). The scorers don't look up this stuff to see if it's correct. I know someone who said the Declaration of Independence was signed in 1789 and he received a perfect score
I know my question was asking about whether people should study a narrow field all the time or if a well-rounded education is a better idea, and I used the creation of Teflon as an example of a scientist having an epiphany while pursuing a passion for cooking. I couldn't tell you when this happened, but I think I wrote a year in the 80's. I also got a perfect score. They love it when you think outside the box and don't care if you fudge a little on the particulars.
I'm also preparing to re-take the GRE. I did wonderfully on the qualitative part, but not so hot on the quantitative part. I want to apply for sociology PhD programs, so I don't need to know any math outside of statistics, but I would like to bump up that score a little
It's kind of unnerving to take this test on the computer!
edit: oops! Didn't see you had already taken it. I'm sure you did well!