Be humble when you want to be humble. That comes easier for some people. Be self-deprecating, complain, bitch, moan, whatever you want to call it. Be careful though because a gripe session can sometimes turn into a bragging session before you know it.
One of my favorite definitions of humility is "being open to the possibility that things are other than the way I think them to be." In this sense, it is one of the absolute keys to change and an essential quality on the path to transformation.
When we can finally come to accept our rightful place in the nature of things, we see that we are neither absolutely divine nor absolutely evil, but somewhere in between. And since that means we don't have to be perfect that's not necessarily a bad place to be.
Be grateful for all of the things you have always hated about yourself and recognize they are now things you have learned to love and appreciate. Be grateful for the life experiences that have paved the way for you to know who you are and who you are not.