There are seven ways of doing this in my life:
Performing group level service.
Performing service in the service structure of the fellowship.
Carrying AA's message to the wider world.
Service to family and friends.
Work as service.
Service to the community and society as a whole.
If you are unhappy, a little work on yourself in inventory, confession, and some amends, prayer, and meditation will be necessary to prepare you for this.
However, service is the point.
I spent too many years in recovery moaning and complaining about my feelings and endlessly dignifying my emotional immaturity and teenage neuroses with hip terminology and complex analysis. That is all very well, but I was missing the prize. Service purifies the soul by fire and burns away all unnecessary self-centredness, leaving only the form God intends.
Happiness does flow from service, but it is not the point. I would rather have a life that is worthwhile because I have made the contribution I was meant to make. This produces a much more sustainable and satisfying happiness. Mahogany, not pine.