How do IITJEE toppers prepare for each chapter and what is their strategy?

This is what IIT JEE toppers do,

1. They follow a disciplined strategy. They love the subjects they are studying.
2. They know their strengths and also work on weaker areas.
3. They focus on concepts understanding and application of logic. When starting a topic, he/she would make sure to study all the related concepts at once and then solve the problems.
4. Go into the root of the problem, understand the concepts instead of memorizing them (some exception to Chemistry).
5. Resolve your doubts quickly. If you don’t understand anything, ask the same question again and again from your teacher. Never procrastinate in your IIT JEE preparation.
6. They focus on quality over quantity.

All The Very Best and Good Luck :)