Cleanliness and Organization
This the core. I like to plan and check where my time is going. Therefore anything that will improve my ability to use my time wisely I opt for. This helps alot because I have numerous side projects.
Exercise and Food
I made it a habit to do at least one physical feat every few months. Right now I'm working on doing 100 pushups. The next is to break a school track and field record. Just little things that require dedication (1/2 hour to an hour a day) but don't interfere with my life. Bodybuilding for example I found negatively affecting my life so I stopped doing it. Food is self explanatory.
Facing Reality
As explained by Robert Abitbol.
Knowledge
I don't want to know everything but I like to be informed about many things. The information is freely available at my school library. Every month, I read about 3 - 5 books that concern philosophy, history, and current events. This also includes breaking mental barriers. I'm a radical athiest but that doesn't mean I shouldn't read the Bible.
Trivialty
It's better not to seek it. Petty and trivial conversations are extremely unhealthy. For example, I find that my floormates in college are very opinionated. Sure you can argue/talk about things (say the Iraq War, the weather) for a lengthy period of time but do these conversations get you anywhere? They say the more people you know, the better off you are. If you consider trivialty, it's better just to stick with a few good friends. Talking about nothing is a nasty addiction, on the same level as alcohol, porn, and cigarettes.
Beauty as the bringer of happiness
Some things are very beautiful. They possess the sort of beauty that is inexplicable to others who are unable to experience the same beauty you do. I actively search for these kinds of things. Music, art, books etc.,
Conventional Wisdom
Avoid it. Avoid passionate groups. Avoid unneccessary things/people that interfere with your ability to be yourself.