I had a very wise biker friend, back in my 20's, that gave me this advice after I had gone through a bad breakup with my live-in girlfriend at the time. I lost my car, my home and my girl all within a day. He forced the idea of living in the moment to find happiness... the way he explained it opened up something in my mind that hasn't gone away.
I feel like for some people this is extremely difficult as so many of us cling on to the past or fret about the future, but both of these anxiety's can be dealt with by living in the moment you are in.
Great advice... it's how we were meant to live I believe.