The purpose of life
Expansion of happiness is the purpose of life, and evolution is the process through which it is fulfilled. If one is not happy, one has lost the very purpose of life. If one not constantly developing his intelligence, power, creativity, peace and happiness, then he has lost the very purpose of life. Life is not meant to be lived in dullness, idleness, and suffering; these do not belong to the essential nature of life.
— Maharishi Mahesh Yogi
Become Self Aware
I think the best way for us to strive for happiness in our lives is to become more self aware. When we know what we are thinking and feeling, truly know, then we will make better, healthier, decisions with our lives.
The best way to do this is reflection and meditation.
Reflect by keeping a journal. Write in it regularly, daily if you can. Tell yourself what happened, what you thought and what you felt about what you are writing. If you're having trouble then just write. Take down the stream of conscious thoughts pouring out from your mind.
Meditating will help you get in touch with your body and your feelings. Sit on the floor or a stable surface cross your legs and roll the top of your hips forward. This will move your hips under your spine and support your back. Relax and breath. Pay attention to your breath. Breath in for a four count, and out for a four count.
There really is no wrong way to meditate. The goal is to calm down and pay attention to your body and your emotions.
Self awareness isn't something that comes right away. It takes time. Reflection and meditation are not quick fixes, rather they are tools you should use the rest of your life to gain happiness.