(2) Literature has a language of its own. Learn it.
To the layman, a comparison might seem like a comparison. But to the literature student, a comparison may be a simile, a metaphor, or a metaphysical conceit. On the Literature GRE, you will encounter numerous specialized terms for poetry, figurative language, and literary criticism. Acquaint yourself with this vocabulary by skimming a reference such a Merriam-Webster's Encyclopedia of Literature. Some students earn a B.A. in English without ever taking a course on literary criticism. But you will need to master the basics before you take the GRE. The Encyclopedia of Literature will be helpful in this regard as well, but a more useful overview is provided in A Handbook of Critical Approaches to Literature (Oxford University Press).
(3) The gods may be crazy, but you would be even crazier to overlook them.
Most literature students could benefit from a refresher course in Greek and Roman mythology. The gods make their way into the works of writers from virtually every time period. They are the subject of allusions and metaphors in both poetry and fiction. A quick survey of Edith Hamilton's Mythology should enable you to supply your literary arsenal with the information you need.
(4) Discover Masterplots.
There is no time to lament all of the classic titles you should have read. You can't read an entire library in a few weeks. But you can read two to three page plot summaries of the most important books you have never read. Go to your local library and take a look at a wonderful, multi-volume reference known as Masterplots. Or, invest in the series yourself—this won't be the last time you use it. This handy series will enable you to familiarize yourself with the classics you've heard of but know little about. When these works make an appearance on the GRE, you will likely know enough to identify them.
(5) Sample.
Although you can and should read summaries of major works, you need to sink your teeth into something more substantial as well. Read just a few select texts from the most famous writers in order to familiarize yourself with their writing styles. This will help you to identify passages on the GRE, even if you have never actually read them before.
(6) Know the biases of the test makers.
Pay special attention to 20th century authors, female writers, and minorities. In recent years, the GRE's emphasis on such writers has increased dramatically. Questions about works and writers of the past century may well equal the number of questions covering all of the centuries from Beowulf to Tess of the D'Urbervilles.