One of the best ways to improve your study skills in remembering the details of a historical event is to make up a silly or ridiculous visual in your mind. For example, if you are trying to remember that the American Civil War was fought between 1861 to 1865 and that the Confederacy's President was Jefferson Davis, while the Union's President was Abraham Lincoln, you can create a silly image in your head of Jefferson Davis riding a surfboard wearing a shirt with a "C" on it while racing Abraham Lincoln on another surfboard wearing a black top hat with an "U" on it. Picture Davis's surfboard having a cool graphic of the numbers "1861," while Lincoln's surfboard has "1865" printed on it. If you need to know more details for an essay question, you could add to the picture. You could have Davis holding a paper in his hand, which says "secession," and Lincoln could be holding a copy of "The Emancipation Proclamation" in his hand. You could picture hundreds of African American slaves reaching up out of the water to grab onto Lincoln's surfboard. Then, you could picture Lincoln wiping out on a big wave to remind yourself that he was assassinated in 1865.
The mental image can be as creative and personal as you want. If you are into skateboarding, Davis and Lincoln could be on a halfpipe! If you are into Guitar Hero or Rock Band, picture Lincoln and Davis jamming away in front of a huge crowd of guys in blue and gray uniforms. Make the picture your own, make it unique, and I guarantee at test time, you will be smiling, not only because you will feel confident that you know your stuff, but also because you'll have this silly image of Lincoln and Davis "hangin' ten" or waging an epic guitar hero battle, or even dancing off in front of an X-Box.