Can mentorship help avoid common prep mistakes?

While preparing for exams, I realized a lot of mistakes don’t come from laziness — they come from not knowing the right approach.

For example, I spent weeks making super detailed notes before realizing many people focus more on practice questions and frequent revision. I also kept switching between resources because every topper recommends something different.

It made me wonder how much mentorship actually helps. Not in a “guru” way, but just having someone who’s already gone through the process and can say things like: stick to limited resources, start mocks earlier, and focus more on revision.

For those who’ve prepared before did having a mentor help you avoid big mistakes or did you figure things out on your own?