Hi student,

It is good to start preparing early for jee mains and advanced. It is one of the toughest entrance examinations and needs thorough preparation. Majority of the portion of JEE Mains and Advanced is based on class 11 and class 12 syllabus. So it is important to pay attention to class 11 and class 12 syllabus. So it is important that you stick to the syllabus and read the NCERT's of Mathematics, Chemistry and Physics thoroughly. Let us take one subject at a time.

CHEMISTRY:NCERT for chemistry is very important as there are several times when JEE has asked direct questions from it. For organic, read all the reactions thoroughly, memorise the reagents and catalysts and clear your concepts regarding their use. The formulae in must be on your fingertips. The physical and inorganic portion must also be thoroughly read. After covering all the topics from NCERT and the reference books,  you must attempt questions from past 10-12 years of jee mains. Several books are available in market like Arihant, McGraw Hill,etc that provide solved previous year papers.
MATHEMATICS: Practice is the key to maths. Once you have covered the syllabus from NCERT, practice questions from books like R D Sharma or TMH Mathematics. Also refer SL loney and Hall& Knight. Honestly attempt the previous 10-12 year papers to enhance your understanding of concepts. Again, the formulae must be on your fingertips.
PHYSICS: Physics is a very conceptual subject. Don't try to mug up things without understanding, as this will be time consuming and not fruitful. Its better to read less but whatever you read is conceptually clear to you. Some of the important books apart from NCERT are H C Verma and Arihant DC Pandey. H C Verma is a must solve book for jee mains. Lastly solve the past years papers for the final touches to your preparation.
One of the most important thing in preparation is joining a full test series of any good coaching institute. It will also increase your problem solving speed which is on of the major rank deciding factors.

Full booklist for jee mains and advanced preparation are as follows:

Best books for JEE Main 2019 -Physics

Hello aspirant

I can help you with better information.

Firstly start preparing 1st puc syllabus.if you complete 1st puc syllabus then there is more scope of getting good score.

Then start preparing for 2nd puc syllabus

Mostly start with chemistry and mathematics and then go for physics.

Hope above information is helpful to you and

All the best

Thank you