You should revise important formulae and important topics with its overview from NCERt books. Review all mistakes you made in mock exams. By this time all fundamental should be great and solve out doubts if any. 

Focus in 2 to 4mock exams at most fromnow and give your best. Post that analysis of strong and weak areas is must to know where you need to work upon more. 

• First try to revise those notes which you have prepared while preparation.
• Take down all the important formula in a single sheet such that before going the exam hall you can revise it well.
• Try to revise the important blocks which are given in every chapter.
• Do the mock test and previous 10 years IIT-JEE paper.
• Stick the important formulae on wall and revise it daily.
• While revising try to focus more on important topics of three domain PCM.