How to obtain a 90 percentile?

People who have scored in the 90th percentile for L1 and L2 (I’m not sure if there’s a 90th percentile for L3), how do you do it? How many months in advance do you study? How many hours per day do you study? Which prep provider do you use? What type of study methodology do you follow?

I am a Financial Engineering student with knowledge in several related topics. English is my second language, and I am truly passionate about everything related to finance. However, I would like to understand how they managed to digest such a large amount of information. That’s why I’m asking all these questions.

I appreciate any information you can provide, and I apologize if this question has already been asked several times before.