Here goes, then, tips for preparing for the exams.
Take a pre-test. Yep, you can get those on the GRE site. Then go through it to figure out where you're weak, and focus on those areas. That may seem obvious, but it's not. Most people want to study what they like to study.
But here's a caveat: if you're going into the humanities, you may think no one cares about your math score. Maybe they don't. But you also don't want it to stand out on the low end, right? And if you're thinking of something like history, then good math scores may be a lot more important than you think at first, because historians use lots of statistics, and you can learn a lot by understanding math well.
In English lit, the only way to really do a bubble test exam is to be pretty canonical. That means some of those courses in really cool lit by marginalized folks won't be represented well. That sucks, and is one of the problems with a test like the GRE.
But since you can't change the system before you get into it, you need to know how to play the game. Do the pre-test, and figure out your areas of weakness. Compare with the statistical breakdown on the site. If you haven't taken a Brit lit survey from 1660-1925, and are weak in that area, recognize that the GRE site claims that the 25-35% of test focuses on that area. Your payoff for studying that area is relatively bigger than for working on the same level of weakness in classical lit.
Also pay attention to the sorts of questions you missed. Do you make the connection between a parody of a work and the work? Do you miss the poetry conventions?
Most of my students are weakest on poetry. They just don't study much poetry here, and when they do, it's usually 20th century poetry, so they aren't at ease with earlier conventions (which sometimes means they don't get the way 20th century poetry plays with those conventions, but don't realize it). Remember, though, that poetry's usual shortness (compared with triple deckers, anyway) makes it lots easier to use on a bubble test.
Once you've figured out your areas of weakness, you need to hit the books. The thing is, you don't need to read deeply for this sort of test, but widely. Get some anthologies. (I used the Norton's a lifetime ago, but Longman's would also be fine.) Read the introductions, especially for the periods you're weak in. Take notes (since writing helps you remember). Read the headnotes for works, and read the works. Think about what makes Marlowe feel different from Shakespeare, what makes Jonson different from Johnson, and so forth. Try to build a sort of scaffold for yourself, and think about how writers fit into broad periods, where they fit in relation to one another. What makes Wordsworth
You don't need to read the whole of The Faerie Queene, but read enough of the first book to get a feel for the verse. (And then you can read the whole thing as a treat someday when you can't get your usual drugs, and try to figure out the circularity of time in Book I.)
Get a list of the 50 most important novels/plays, and then visit your local academic library and look at Masterplots/Masterpieces. (These are a series of volumes with abstracts or summaries of works of literature. Because, really, do you want to read Dickens?)
If you can get a group together, get a group together. When I studied for the GREs, my group assigned a different piece to each person for presentation. I still remember Tintern Abbey with something less than hatred because the guy in our group loved it so much that I got a little bit of that.
All that work for a stupid test?
Yeah, I don't know. My score went up by 100 points from the pretest to the real thing after most of a summer of studying, and I think my test scores helped me a lot getting into a better grad program, especially since I was coming from a little regarded regional university and competing for a spot with folks from ivy league schools. (The grad studies person in the department once commented on my scores, so I know he had paid attention to them; I was also one of--I think--4 people from a public school in my entering class of 28, and that counts Oxbridge as a public school.)
The really worthwhile thing about the summer of studying was that I got a broad overview of literature in English, and that was a great starting point for graduate study in English. After taking that test, the next year's classes (while I was applying to PhD programs) just made so much more sense in terms of patterns of repetition, change, and development. It's like the richness of my experience made literature even more interesting.
What do you recommend for students preparing for the GREs? How do your recommendations for the subject test (especially in non-lit) vary?
What's the single most useful tip you could give?