You have to learn the rules of the game to play it better than anyone else (Albert Einstein)
I have seen this idea repeatedly on forum wrt cracking civil services exam and I think I know some rules like fixed (and minimum) sources, revise as much as you can, take mocks regularly, etc. but I do not think if I know all the rules, probably because I have not had much experience with this exam
So, I request all the enlightened members to please take some time out and tell aspirants like me what exactly are these rules (esp wrt mains stage) and how they made amends in their preparations accordingly.
Finally, Happy new year and All the best