To be admitted to the ASVAB testing room you will need to show a valid id. It is also important to be on time (or early!) since you will be turned away if you show up after the scheduled start time. The ASVAB can be given via computer or pencil and paper. If you are testing at a MEPS site you will take it on a computer. The pencil and paper version is given at most MET sites. The computer version of the test is given as a "computer adaptive test" (CAT) which means that the test will adapt based on the level of the individual test taker (e.g., if you answer many questions correctly, you may be shown fewer questions).
I have already served in the military years ago. But I wondered if there was a primer that might have helped me improve my test scores. I think this book would help. Unfortunately it's hard to learn enough from a book to do well on the math and reading comprehension of the ASBAB test. Study hard in math and English class in high school. It's hard to cram from a book to pass a comprehensive test that covers many topics. I think it may give you a few extra points, however.
Don’t let the PC section of the test throw you for a loop. Unlike the individual multiple choice questions in other sections, here you will need to read a paragraph and answer several questions in a row based on that one paragraph. The people who designed this section of the exam really knew how to make sure you are able to read detailed (and often boring) documents, remember the details of what you read, understand why they’re important, and be able to pick out the key concepts they illustrate. When you read each paragraph, it’s helpful to know the kinds of questions you’ll be asked at the end. There are basically four kinds of questions to test your comprehension: