Hey kiddos, I'm a professional ACT/SAT tutor with over 5,000 hours of tutoring experience. This post is adapted from a comment I made on another thread here, but I figured it might be useful for a wider audience!

Here are some suggestions for the last couple of days before this test!

1. Get lots of sleep. Most young adults your age need between 9-10 hours of sleep EVERY DAY for optimal cognition. I recognize this is hard to achieve with homework, extracurriculars, and a social life, but prioritize sleep for the few days before big tests. If you are chronically sleep deprived, this is BY FAR the easiest thing you can do to increase your score. I had a chronically sleep-deprived student (he was averaging 5 hours of sleep a night) go from getting 29s on practice tests to a 35 on the real thing simply based on getting a full rest the two nights before the test. It matters.
2. Prioritize your mental and physical health over the next few days. You will be at your best if you are feeling good mentally and physically. So, make sure you are on top of your schoolwork. Go hang out with your friends. Avoid screens after 9 PM. Get some physical exercise! Do what you usually do to de-stress.
3. Do some light review of math topics you find tricky or difficult. Go over questions you have missed on your most recent tests - remember, past mistakes predict future mistakes, and past questions predict future questions.
4. DON'T grind another few tests. At most, if you are really really feeling it, you could do an english math section, grade them, and then review mistakes on that test and other recent practice tests. Don't do more than this in the last two days, it will likely be counterproductive.

For the test:

1. Remember that you can't control everything. Worry about what you can control, not what you can't control.
2. There are a few options wrt mindset. Option 1: Get mad. "Fuck everyone, fuck the doubters, fuck this test. I'm here to prove a point." Option 2: Super chill. "If I do well great! If not, there's always next time. Low pressure." No matter what, don't go in thinking "this test will make or break my life" because 1. that's not true and 2. it's just piling on unhealthy stress on top of the healthy pressure you should feel anyways. Don't make it harder on yourself.
3. Never ever let a rough question or a rough section affect the rest of your test. Try to avoid tilt. I had a student who got 75/75 on the English, then got stuck on question 56 of the math section, didn't hear the proctor say "5 minutes left", and had to guess on the last 5 questions. This fucked up her mentality and she spiraled out of control on the Reading and Science. She ended up getting a 36 on English, 29 on Reading, and 26 on the Science as she cried her way through the section. The irony? She got a 35 on the Math. She let her perception of a bad section destroy her entire test.
4. At any point there are only two factors that matter: The question in front of you, and the amount of time remaining on the section. Nothing else is ever relevant. One question at a time.

Good luck!