Whatever we choose to care about we focus on.
Whatever we focus on we create.
If you want to be happy all the time, don't care about any "thing" more than you care about being happy and you will be happy all the time.
If you want to create a certain result in your life, don't care about any other "thing" more than you care about the result you want, and you will create that result (unless you die first of course).
