One of my tutors said to treat the books like you would the tests, and time yourself. I think that was the biggest reason why I managed to pass the test, as I not only took the tips and advice from the books (which imo, the N2 reading book is so worth it!), which helped speed up the process and get me to narrow down answers easier, but I also got used to the speed at which I needed to answer the questions. Come test time, I had already done dozens and dozens of questions in the exact same way, so I knew exactly how to handle them. (My score wasn’t great, but hey, I passed! xD)
I used the timings from this page to judge how long I had per question: https://jlptbootcamp.com/2011/06/jlpt-time-time-management-for-the-test/
I also second Matt’s advice. I went through several questions with a tutor, untimed, where I’d read the text out loud and guess my answer, and she’d explain if I got them wrong. She helped me identify more tips and clues as to how to find information and narrow down answers.
Good luck! You got this