Many students ask me question "is there any shortcut methods to solve a question?" actually I want to refer to the answer of this question. First of all, shortcuts is not acceptable by your board exams. If you are not writing with proper understanding, you won't be able to get full marks even after solving that question and also after getting correct answers. Shortcuts is not a best method to solve a probem in exams but when it comes to competetive exams, shortcuts have much more gratification.
How to get shortcuts?
Well, whenever trying for a problem, just try to calculate in your mind and write it directly on the notes. Just trying to short the steps is called a shortcut.
Memorising all the formulae and some of the answers too of basic type questions so as to get the answer easily and correctly is one of the shortcut.