We’ve all heard the horror stories: John was forced to take the SAT twelve times. Mary got a 34 on the ACT, but only after her ninth try. Will these multiple attempts hurt John or Mary’s chances of admission, or was it better for them to take these tests as many times as necessary to get the scores they needed? How many times should you take these tests, and will too many attempts look horrible on your application?

Fortunately, the answers to these questions are very simple, once you understand the basic processes behind these tests, and the roles that they play in the admissions process. With that in mind, let’s launch right in. The first thing that parents and students need to understand is:

1. You should never take real SATs or ACTs “to see how you do”

This is the biggest mistake you can possibly make. I can’t tell you how many anxious parents have approached me with horrible first-round scores and told me something like this: “Matt never had any prep, and we didn’t know how he’d do, so we had him take a real SAT to figure it out.” This is like shoving your face in a hornet’s nest to see if you’re immune to hornet venom. There are less painful, less risky ways of figuring this out.

Want to know how you’ll do on your SAT or ACT? Both the College Board and the ACT publish books with real SAT and ACT tests and real grading rubrics. Get the official books, learn how to take a realistic, timed exam, and grade it. What you get is where you stand.

As you keep prepping, you should keep taking realistic diagnostic exams. Your scores on your diagnostic tests will roughly match the scores you’ll get on your actual test. Which leads me to my second key point:

2. Don’t take your SAT or ACT until you know what scores your target colleges are looking for, and until your diagnostic scores match them.

Prep until you get there.

If you know that your target schools require a minimum of 600 in each section of the SAT, and you’re not breaking a 500 in any section, don’t take the real thing! When you start breaking 600 on a routine basis, then it’s time to take your real tests, but not until then.

The SAT tests one thing: how good are you at taking the SAT? The ACT tests one thing: how good are you at taking the ACT? You need to prep for these exams (I usually recommend following a self-guided online program, then supplementing with one-on-one tutoring if you need to fine tune your results). But if your scores don’t match your targets, keep prepping until they do. If your scores are vastly lower than the scores your target schools require, you need to either a) prep harder, or b) find less competitive schools.

Also, before you start prepping for either test, figure out which one you need to take. Which leads me to my third point:

3. Do not start studying for the SAT or the ACT until you figure out which one is best for you.

Students are predisposed to take one test or the other. I’ve never tutored a student who didn’t have a strong preference for one exam over the other. Figure this out before you launch into a prep program. Read my full, free guide on how to do so.

Once you figure it out, you can start prepping.

Let’s say that you’re trying to get an 1800 on the SAT. At first, you were only getting a 1400, but after prepping for a while, you’ve hit your mark. Your last few diagnostic tests have given you a 1790, an 1830, and an 1810. Now it’s time to take the real thing. Before you do, read Part Two of this article, detailing why colleges care about test scores.