Know what to expect on the Compass Reading test. Knowing what will be tested will help you identify what you need to study. The test is a multiple question test that, according to ACT Compass.org, "evaluates your reading comprehension and vocabulary." These are the key angles you need to focus on.
Improve your reading comprehension by learning how to break down reading passages into smaller sections. Practice reading a small story or magazine article. As you read, stop every so often and mentally recall what you just read. When you reach the end, think back on the entire passage and vocally summarize it. Reading comprehension is the level of understanding you have of a passage after you read it.
Brush up on your vocabulary for the Compass Reading test. Keep in mind your vocabulary doesn't have to be at a scholarly level. You are applying for college after all, but, a little improvement will help you score higher on the test. One of the best, and cheapest way to improve your vocabulary is to become familiar with Latin and Greek. Latin is the root of many European languages, including English. Knowing how to dissect a word and understand the meaning of that part will help you figure out the word meaning. For example, the word hydrate contains the root word "hydro" which means water. You can insinuate that the word hydrate has something to do with water. This is extremely helpful since the vocabulary part will be you finding the meaning to complicated vocabulary words.
Take practice Compass Reading tests. You can find some test question samples at act.org/compass/sample/pdf/reading.pdf. The sample questions include a passage to read, followed by questions about the story. They are multiple choice questions, just like the real Compass Reading test. Check with the college you are applying to as well. They often have practice tests available for incoming students.
Get plenty of rest the night before the test. Study before bedtime, then set your alarm and go to bed. Feel free to scan over anything you feel you need to in the morning before the test.