For Accountancy, one needs to have a clear idea about the syllabus, cover each chapter thoroughly as the questions may be direct or indirect, note down the formulas and principles of accounting separately and study it again and again.
Once finished the whole syllabus revise it again as many times as possible.
By now you must have done your calculations as to how you will prepare for this subject. And most you must have even finished studying for it and now must be revising.
February is the ideal time to start solving sample questions papers to master every subject and gain perfection in time management as well.
Below is the sample question paper of Accountancy set by CBSE. There are three sample papers along with the answers at the end of each of them.
Try to solve at least one question paper daily to master the subject of Accountancy.
Click on the link for Accountancy sample papers by CBSE — http://cbseacademic.in/web_material/Circulars/2012/47_ClassXII/J_Accountancy_XII.pdf
NOTE: Get History sample question papers by CBSE tomorrow morning.