Don't study only the minimum that is necessary. Study more. If you have excess knowledge on something, you may remember it better. Suppose you are looking up a word that you do not understand. Do not just stop after you have read the definition; take a few minutes to look for examples of the word as it is used in a sentence.
If you are studying complicated information that you know nothing about, try to link it to a topic that you are very familiar with. You will be able to recall the unfamiliar material much better if you are able to associate it with something that is easy for you to understand.