Studying for the GRE

Taking more than one official GRE exam is time-consuming, difficult, expensive, and probably not very effective. A better strategy is to take several self-directed practice tests. Every year, practice tests are published both in book form and on-line. These self-given practice tests are useful for a several reasons:

They provide excellent practice at applying your test-taking strategies.
They let you become familiar with the different sections of the exams and their instructions. On test day, you can save time by skimming instructions rather than reading them thoroughly.
Performance on practice exams shows where you are weak. You can better focus your study time by working on those areas.

Getting the most out of your practice exams

You should not try to work an entire exam in one sitting. A better approach would be to work one complete 30-minute section in a given session. Then, take a full hour to check your answers and review where you went wrong.
Before starting each unit, review the appropriate verbal or math basics and the strategy for that type of item.
Work through the section with standard test timing. Keep an eye on the clock. When you start to run out of time, return to the questions where you eliminated several choices. Select one of the remaining choices. When you make a choice but are not confident that it is correct, mark any other choices that look almost correct.
After time runs out, mark the questions that you did not have time for. With no time limit, finish all these questions as best you can.
Grade the unit using the answer key.
After a short break, and while the questions are still fresh in your mind, go over each item. On items you missed, can you see what you did wrong? Are there particular types of questions or topics that gave you more trouble than others? If so, flag them for more study.
Keep in mind that the reason for reviewing the test is to find if your approach to that item was correct. If not, how did you go astray? Did you read carelessly or too fast, fail to underline or mark paragraphs properly, or get drawn into a trap?
Keep in mind that the quantitative items are usually direct, even when difficult. But with the verbal items, it is necessary to become comfortable with the type of thinking that leads to the correct choice. Review the reasoning that led you to each wrong answer and see how you could have handled it correctly.
Work through all sections of one practice exam before going to the next. Calculate your final score for each section and for the entire test.
If all went well, on the next exam you will work more quickly and (hopefully) see an improved score.
Knowledge is the main factor for the Subject Test. The best way to review psychology's most important concepts is to study a large introductory psychology textbook. Concentrate on the summary and key terms for each chapter.