You need to wake up and realise that everything is going to end one day. Everything that has ever happened till this day, till this very moment, does not exist anymore. Whether pleasant or unpleasant, good or bad; no matter what happened till now, it no longer exists. It is all finished.
As we go ahead in life, we will realize that everything is going to end. Nothing will remain. And yet, we still sit and go on thinking over it, worrying about this and that. Shake everything off yourself, just wake up and see – there is nothing.
Everything is nothing, that’s it. This very realization is enough for wisdom to dawn within you. The nothing that remains is what everything truly is. You need to remind yourself of this again and again so that it gets instilled in your memory. Just see how you have surpassed all in the past and moved ahead. “Everything is Nothing”- this is called the Hridaya Sutra (aphorism of heart) as was told by Lord Buddha.
This is also what Adi Shankaracharya called the philosophy of Advaita. All five elements are nothing. The five senses are nothing. I am nothing. You are nothing. Devotees say the same thing in a different way. They say, 'I am akinchan' (I am nothing). If you just understand this, great awareness dawns within you. So whenever something worries you, awaken yourself.
Remind yourself that one day we all have to die. No matter how much you decorate and adorn this body, one day it will burn on the funeral pyre. See every problem as a challenge. Take it as a challenge and see. Then there is no power in this world that can wipe the smile off your face.
To know this, how many books will you have to read? What all will you do, where will you go? You don’t have to do anything. People have gotten so tired asking again and again, 'What do I do?' And the gurus who keep saying, 'Do this, do that, do this', have grown tired of saying it. So you have to do nothing. Just know that all this is nothing.