>>1327583495% just do practice problems. Old tests are best but if you're not at that level yet find books. I started with this one, it's relatively beginner friendly.
http://library.lol/main/FFBAD5284A0F4B5BBDDC61919383A528This one's also interesting, the problems are for ~13 year olds so they're much easier but still have the same 'feel' in that you need to be creative and figure out the right angle to approach it from instead of it being a straightforward homework problem.
http://library.lol/main/929CFABEC3568F2E559ED1294D7C1490For the old tests the solutions you find online are very terse and unenlightening. The official books have much, much better explanations.
http://library.lol/main/00C288FF3617217A9752B1E6005B719AAs for subject matter don't try to learn it just for the test. The level of fluency you need for the test is higher than you need to do a regular class, so it's a waste of time to try to quickly learn a subject just for the test. Learn it properly first, either in a class or independently, and in the meantime just accept that you have no shot at a lot of the problems and focus on the rest.
t. 2x honorable mention