There are some common thing you should follow to score better in your board examination. They are:
1. Make a strong grip over NCERT books. Do each and every question from all those chapters which are included in your syllabus. There is not a single question which comes out from NCERT book. You can read or download NCERT books for class 10for quick revision.
2. Notes of each chapter are very important for quick revision. If you have made it than it is ok if not then don't waste your time in preparing notes at this time when your exam is near. Go online for notes of each subject. You can get class 10 science notesonline.
3. If you have done these things, now it'* time to solve more and more questions. First, solve CBSE sample papers for class 10 which CBSE board releases every year officially. Then solve at least the previous 10-year board question paper from the question bank.
4. You can also revise math formulas for quick revision of mathematics section. Refer here math formula.
If you follow this strategy then certainly you can score much better in board exams.
"All the best for rest of things."
