Did you put off your happiness when you were young so that you could be better off when you grew older? Did you enjoy it as it went along? Do you get happy from big things? Little things?
(I've found that you need to know a thing 10x as good to teach it as compared to simply using or applying it, so teaching would make me very happy indeed but I don't know much well enough to be able to effectively teach it).
The little things add up to big things. A big source of personal happiness for me is to leverage our unusual work schedule so that my wife and I can take walks together in daylight in our neighborhood and enjoy uninterrupted conversation. The kids are older now, so they can be left alone long enough for us to do that.
Repairing stuff.
Kids.
Learning.
(I've found that you need to know a thing 10x as good to teach it as compared to simply using or applying it, so teaching would make me very happy indeed but I don't know much well enough to be able to effectively teach it).