Weapons of mass happiness:
Love, Forgiveness, Kindness and Non Judgment.
That is the long and the short of it.
All the "Stuff" you need for happiness.
Don't forget to play and have fun on your journey. The journey is never over until you die. You will never be perfect about anything. Trying to be perfect blocks improvement. It is a "perfect way to never accept or love yourself". Accept yourself where you are right now and set your sails on living a life of love. Some days you will fail miserably and others you will success. Come to understand and accept that all of us have a full complement and full access to both Love and Hate. It is up to us to become conscious of our shadow side and make the choices we can, moment by moment, to live from the loving side.
When you get to where it becomes an automatic habit to apply love, forgiveness, kindness, and non judgment, "verbs of action", you will be the happiest person on earth. In the meantime accept plenty of "do overs".