HSC Exams starting from 21st Feb is an important exam. Please dont take it lightly. Everyone knows that getting into Engineering College requires only 45% in HSC PCM and 35% in other subjects but then too i suggest score as much as u can as I will help you in your Post Graduate Admissions. Sounds Funny But TRUE

English:-
This is a very Easy Subject. Here you can score 70+ easily provided:-

  1. Read 2-3 Poems and relevant comprehension questions
  2. Same for Passages and Rapid Readers
  3. Last 2-3 Years Essays topics Find relevant Information from Internet
  4. Basic 10th Std. Grammar
Still you have time then Buy Navneet 21 sets and go through once. Thats it for English. English requires not more than 5-6 hrs of studying a day before your exams.

Physics:-
Physics I - Hsc Weightage - Marks Without Option (Marks With Option)

1. Circular Motion - 4 (6)
2. Gravitation - 3 (5)
3. Rotational Motion - 4 (6)
4. Oscillations - 5 (7)
5. Elasticity - 4 (6)
6. Surface Tension - 4 (6)
7. Wave Motion - 3 (5)
8. Stationary Waves - 5 (7)
9. Kinetic Theory of Gases - 4 (6)
10. Radiation - 4 (6)

Physics II - Hsc Weightage - Marks Without Option (Marks With Option)

1. Wave Theory of Light - 3 (5)
2. Interference And Diffraction - 5 (7)
3. Electrostatics - 5 (6)
4. Current Electricity - 4 (6)
5. Magnetic Effect of Electric Current - 4 (6)
6. Magnetism - 3 (4)
7. Electromagnetic Induction - 5 (7)
8. Electrons And Photons - 3 (4)
9. Atoms,Molecules And Nuclei - 4 (6)
10. Semiconductors - 3 (5)
11. Communications - 2 (4)

I will suggest you to prepare looking at the weightage as each student have different strategy.
My Suggestion:-
Physics 1 :- Chp 1,3,5,7,8,9,10
Physics 2 :- Chp 1,3,4,5,6,7,10 

Chemistry :-
Chemistry I - Hsc Weightage - Marks Without Option (Marks With Option)

1. Solution And Colligative Properties - 7 (10)
2. Chemical Thermodynamics And Energetics - 9 (12)
3. Ionic Equilibrium - 7 (10)
4. Electrochemistry - 6 (10)
5. Nuclear Chemistry - 4 (10)
6. Chemical Kinetics - 3 (6)
7. D-Block Elements - 4 (6)

Chemistry II - Hsc Weightage - Marks Without Option (Marks With Option)

1. F-Block Elements - 3 (5)
2. Halogen Derivatives of Alkanes - 10 (14)
3. Organic Hydroxy Compounds - 5 (8)
4. Ethers - 2 (3)
5. Aldehydes And Ketones - 5 (8)
6. Acids And Esters - 4 (5)
7. Amines - 3 (5)
8. Biomolecules - 4 (6)
9. Synthetic Fibres - 2 (3)
10. Chemistry In Everyday Life - 2 (3)

I will suggest you to prepare looking at the weightage as each student have different strategy.
My Suggestion:-
Chemistry 1 :- Chp 2,3,4,6,7
Chemistry 2 :- Chp 1,2,3,4,5,6 (optional 7,8)

Maths :-
Mathematics I - Hsc Weightage - Marks Without Option (Marks With Option)

1. Mathematical Logic - 6 (9)
2. Matrices - 3 (6)
3. Pair of Lines + 4. Circle - 8 (16)
5. Conics [ Parabola + Ellipse + Hyperbola ] - 7 (14)
6. Vectors - 8 (13)
7. Three Dimensional Geometry [ 3D Lines + 3D Planes ] - 3 (6)
8. Linear Programming Problem - 2 (4)
9. Probability - 3 (6)

Mathematics II - Hsc Weightage - Marks Without Option (Marks With Option)

1. Limits + Continuity - 6 (9)
2. Derivatives + 3. Application of Derivatives - 11 (19)
4. Integration + 5. Application of Integration + 6. Definite Integration - 11 (22)
7. Differential Equations + 8. Application of Differential Equation - 5 (10)
9. Numerical Methods - 3 (6)
10. Boolean Algebra - 4 (8)

I will suggest you to prepare looking at the weightage as each student have different strategy.
My Suggestion:-
Maths 1 :- Chp 1,2,3,7,8,9 (if you do chp 5 you can skip chp 7,8)
Maths 2 :- Suggestion Do ALL. As unpredicted questions comes here often.

Biology:-
Personal Suggestion DO ALL. Attempt as much as you can as since its almost a theory paper mixing up in theory questions is often

Vocationals (Computer Science/Electronics/Electrical Maintenance/Mechanical Maintenance) :- 
Past 5 years papers ALL Questions (Feb/March + Spet/Oct) and some other Important Question which you feel and which is relevant in other years can pas you easily

This is the Last Year of HSC Exams so chances of getting Easy and Frequent Questions is High .
So Keep Your Hopes HIGH and Prepare for the Best.

ALL THE BEST!!