Nice phrase, well i am sure it's harder to be happy if you are poor compared to if you were a millionaire. But more success, more money, will not bring you happiness. If they do, it will be short lived, so the question is then how do you be happy? Very simple, you just decide to be happy. You don't need to wait for something to 'happen' to be happy. You don't need to be in your dream relationship with the love of your life to be happy. You don't need to own your dream car, boat, house to be happy. You simply decide.
That right now, at this moment you are happy. As you're reading this, just smile. And see how that changes your emotions.
Lastly, you become happy first, and then successful.