Hi Ram Mohan Nayak !

Here are the few tips :-

1. Solve the three official CBSE sample papers thoroughly.

2. Take time to absorb the marking scheme (Blue-print).There is a very little chance that the paper comes out of the blue-print like it came in my time but nonetheless understanding how paper will be set can turn things better for you.

3. Never undermine the importance of graphs!

4. Solving the last 10 year question papers of DELHI region, OUTSIDE DELHI and other regions will make your 90+ score sure shot. Many of the times, the 1 and 2 markers are direct lifts and you can see there are many repetitions. The one markers if you are stuck somewhere.

5. Underlining is important, as when you are done with the chapter, you just have to read the underlined sentences to get the main gist of the chapter. Boosts your revision really well.

First make sure, your concepts are clear. Take a notebook and write only formulae of all chapters that are required to solve numericals. Practise derivations. If you feel NCERT has complicated the derivations, you may take help from SL Arora.

Recommended Books - NCERT and SL Arora

Try to solve all examples and exercise questions given in NCERT. You also need to solve 5-6 previous year CBSE Physics questions to boost your confidence.