But I think that as time goes on, you can make positive changes. Everyday as soon as you get up, you can develop a sincere positive motivation, thinking, 'I will utilize this day in a more positive way. I should not waste this very day.' And then, at night before bed, check what you've done, asking yourself, 'Did I utilize this day as I planned?' If it went accordingly, then you should rejoice. If it went wrong, then regret what you did and critique the day. So, through methods such as this, you can gradually strengthen the positive aspects of the mind.

— Dalai Lama

from The Art of Happiness