Studying by sight
Visual learners remember colorful emotional images best. Make a picture of a bright, loud religious revival in your mind when you read about the First Great Awakening. You may people the scene with Jonathan Edwards holding a sign that says "1730 — Revolution's Coming." That's visual learning.
Be a poet, and you won't blow it
The secret to remembering a varied assortment of facts, dates, ideas, and so on is mnemonics, the art and science of memory. (Naturally, just to mess with your head, the big brains over in the Word Design Department picked a word for memory that's both hard to remember and tricky to say. Just pronounce it without the first letter, and you'll be close enough.) Mnemonics is the psychological system you can use to get ready to score on the big exam.
For example, most people have heard this mnemonic: "In 1492, Columbus sailed the ocean blue." Sadly, basing an entire essay response around this fact is hard. But it's a hint: You can make facts as stick-to-your-brain as a song in your head you just can't stop singing. How about this one? "Thirty days hath September, April, June, and November. When short February's done, all the rest have thirty-one. . ." When is the last time you used hath in daily conversation? But there it is, stuck in your brain.
In addition to bad poetry, you can make up first-letter lists. Did you ever wonder Will A Jolly Man Make A Jolly Visitor? Bet not, but the first letters of those silly words help you remember the first eight presidents: Washington, J. Adams, Jefferson, Madison, Monroe, J.Q. Adams, Jackson and Van Buren. In the same way, HOMES can help you remember the Great Lakes: Huron, Ontario, Michigan, Erie, and Superior. This technique may sound stupid, but what's not stupid is being able to remember an impressive list when AP time rolls around.
Writing key events into your own notes helps fix facts in your mind. This technique can be especially useful for timelines. History is, at its core, the study of change over time. Write out a timeline for major topics so that you can see the big picture of how the changes in one field developed. You could make a timeline of women's rights, U.S. expansion, the 50-year run up to the Civil War, and other key themes.
Flash cards don't work for everybody, but they have saved more than one determined student on the AP exam. At the very least, you get to write down terms and their meaning one more time. The more you write stuff down, the better you'll remember it. You may want to color-code your flash cards by era. Just don't go overboard and spend more time decorating beautiful flash cards than using them. (Although the web has lots of useful flash card and multiple-choice apps you can download, it helps to actually write the words to remember them.)
Studying is a great example of instant karma. Research shows that students who put 50 percent more time into preparation do 50 percent better on big tests.