1. Read Definitions and understand Definitions (Rule 4). You will not understand the rules of basketball or any other part of the rules of basketball if your understanding of Rule 4 is limited.
2. Buy the Athletic Rules Study Program. It is probably too late unless you order overnight mail, but that is the best program. But if the test is a NF test, they tend to ask the same questions year in, year out. ARS is the best tool to understand the repetitive questions. You will get half of them right from this alone.
http://www.rules-study.com/
3. Other than that, you are not going to do very well on your first try. Not to say you cannot pick up on the rules, but it takes some time to understand the language, the terminology and to understand what all those words mean. Mainly because it is hard to visualize what is on paper without some experience. Basketball is not the hardest rules to understand in the world, but understanding what you have never experienced is very difficult. So if you do all the studying in the world, you might not do very well on the test. And if you do, you have some great memorization skills, which you might just have.
Peace