You can solve a problem better after identifying it. The following questions will help you identify where are you going
wrong.

 Are you forgetting formulas in exam?

·
Make a sheet enlisting all important
formulas.

Are you making silly mistakes in the questions you already know?

·
Make sure to learn from the silly
mistake and ensure that you do not repeat it.

Are you not able to solve certain types of questions?

·
Make sure to do ample of questions of
that type.

Are you not able to solve problems of a particular chapter?

·
Make sure you saturate yourself with
all possible problems of that chapter from all available standard textbooks.

Are you not able to solve questions fast?

·
Make sure you do regular revision and
practice questions with a clock beside you to time yourself.

The idea is to analyse every paper you solve. Analyse your mistakes. Think of
questions like

1.
Where did I go wrong?

2.
Did I make silly mistake?

3.
Is it that you find it difficult to solve questions of a particular chapter?

These questions will help you
find the issue and perform better.

All the best for JEE Advanced!