tips to crack any exam?

You always see in social media, internet, in your friends circle, relatives there is someone who crack a exam or a particular thing which you not ever had dreamed of and feel that I can also achieve that thing. 

After that you ask or interview lot of people and at the end comes with lots of different

suggestion and try to implement it on yourself with lots of different resources and also putting lots of hardships but still fails, why? 

There is a famous quote, 

"A bird in the hand is worth two in the bush "

These imply when do two things simultaneously, putting lots of hardships then also you fail. 

So try to focus on one thing and try to master it and if you feel it won't work then try to introgate yourself and resedule it and again focus on it and try to master it and at last you definitely win.