Getting 700+ on the SAT Reasoning
Math Section
The SAT Reasoning test or SAT1 mainly consists of three math sections, two 25 minutes long, and one 20 minutes long. There can be four math sections in the test (three 25minute and one 20minute). In this case, one of the 25minute sections will be experimental for future tests and will not be scored. You won’t know which one is the experimental section, so you must work on all of them.
There are 54 questions in total (not counting the experimental section); 44 of them come in form of multiplechoice questions, and 10 come as gridin (studentproduced) questions, in which you would calculate the answer and right it down on the answer sheet. All the 10 gridin questions come together at the end of one of the 25minute sections.
For each correct answer, you get a point. For each wrong answer, you lose ¼ of a point, except in the gridin questions, where wrong answers do not affect your points. The points are then counted and converted into a score between 200 and 800. The difficulty of questions rise as you move from a question to another within a section. You will not need a graphing calculator for this test. A basic calculator should be more than enough.
The College Board divides the content of the math part into four categories:

Numbers and operations: 1113 questions

Algebra and functions: 1921 questions

Geometry and measurement: 1416 questions

Data analysis, statistics and probability: 67 questions
If I had to compare the Math of the SAT Reasoning test with something we’re familiar with, it’d be the math of the Qudurat test (in Saudi Arabia) in the way it requires more practicing than actual studying. The math in the SAT Reasoning is based on high schoolmath principles you should be familiar with. You don’t need to learn something new. Even if you forget some of the principles after a gap year, for example, you just need to recall them—through your highschool curriculum, Google, or other educational websites like Khan Academy.
Recommended books:

Dr. John Chung's SAT Math: 58 Perfect Tips and 20 Complete Tests:
This was probably the most helpful book for me. The tips may be helpful if you wanted some techniques for
solving the questions the fastest way. But really, the most useful part of the book is the 20 complete tests. The
level of the tests is slightly harder than the actual SAT test, but that means that once you get used to its level
and master it, the SAT level will become a piece of cake.

The Official SAT Study Guide:
The sample tests in this book carry almost the same difficulty level as the real SAT test, which makes them a
very useful tool to get used to the test.
My personal experience:
“Practice, practice, practice”, used to say my foundationyear math teacher at the end of each class. Practicing is the most effective thing you can do to boost your score to 700+. Here the personal way I used to practice:

Start with the harder, Dr Chung’s book
I may have begun practicing from the Official SAT book in the beginning, but at some point I devoted my time for Dr Chung’s. I personally used to take a complete test (3 sections) from Chung’s book every day. There are 20 tests in Chung’s, so that was 20 days of very useful practicing. The harder level of the book will help you master the SAT Reasoning math and actually prepare for the SAT Subject Math. I did find myself struggling in the first few tests, but as I kept moving and stayed devoted, I got used to its level.

Time yourself and remove all distractions
Mastering your time in the actual test is very crucial. This is why you should time yourself when taking the practice tests and find a proper place where you can sit and take a complete test without distractions. Go through the questions as if you were in the real test with the time limit, which means not wasting a lot of time on a single question but doing as much questions as possible instead. Once time is up, then you can go back to the questions you skipped and check your answers. Since the difficulty of the questions rise as you move through them, you shouldn’t spend the same time on the first questions as the last ones. The best way to adopt to this is to continue practicing!

Return to the Official SAT book
Once I was done solving Chung’s sample tests—a few days before the real test, I went back to the Official SAT book to finally adopt and prepare for the actual level of the test. I noticed a huge improvement in my practice test’s results in this book compared to those before I started my dedicated practicing.
General tips:
The above was only my personal experience. It differs from a person to another, with different study materials of course. But in general, know that:

“If you want something done right, do it yourself” –CharlesGuillaume Étienne
Be willing to do the work yourself. Don’t wait for a teacher or anyone to ask you to practice or study.

Don’t be afraid of weird, hardlooking problems
They don’t need much more knowledge. There is always an idea or trick behind each hardlooking problem, and knowing that idea can be very useful in solving future questions. So don’t ignore a problem just because it came in the end of a section or because it looked hard. Learn how to solve it.
Best of luck!