In a word, Marcus says the examined life is a life without guilt; a life with a clear and clean conscience.
We ought to examine our life and we ought to be mindful. And as we examine our life and keep mindful, we will be quick to clean any wounds or ulcers.
Years ago, I heard that this daily practice of being mindful and keeping a clean conscience is like brushing your teeth. You ought to do it every day. You cannot simply say you'll brush once a week and be alright - it just doesn't work that way.
Practice the examined life (exercise the discipline of assent) and be mindful.