For me, the best I can do is remind myself of the dangers of expectations and try to be thankful when it works outs.
For people, I remind myself that they don’t owe me anything, and I try to focus on what I have rather than what I might otherwise like.
I read Elizer's Fun Theory, I thought, "It's better to have no expectations than to disappointing me." So my expectation would be to have no expectations... at all... all the time. It seems difficult. On the other hand, I also have less pleasure in being surprised.
Another option might be to clearly define my expectations, how do you manage your expectations?