-

Having common courtesy can go a long way. Being polite to the person behind the cash register at a fast food restaurant or a grocery store, holding the door open for people, etc.

Not be a bitch.

I think we grow as people when we look for ways to make ourselves happy that don't hinge on the actions, decisions, or opinions of anybody else. Nobody is consistently going to sing your praises, but as individuals we can get in a consistent routine of doing things that make us feel good. Relying on somebody else to make you feel happy is hardly impossible, but it usually leads to feeling even shittier when you're down in the dumps.

Being more empathetic helps.  People tend to get too hung up on themselves to notice other people's problems.

Enthusiasm is very keen to me.