I've heard the idea many times that as we approach Pesach we should be worried not only about the physical chametz in our houses but also the spiritual chametz (hubris etc) that we carry in our souls. I realize that the best approach to addressing this is probably to engage in a deep study of middot, but are there smaller, incremental things one can do to at least start down the path? Where does one start -- what are the right sources to study or prayers/practices to take on?