When in the Our Father we pray, Thy will be done, on earth as it is in heaven, we must take the words on earth as first of all applying to ourselves. Even on the natural level we have enough incentive to reject our own will in favor of God's will--for we have spent enough time carrying our own selves as a burden to know that our own will is neither trustworthy nor directed to genuine joy, freedom, and perfection.
This is why it is critical for us to take advantage of as many of the small opportunities to renounce our own will in the course of a day. Not that these miserable little penances really matter--and we shouldn't dwell on them as it is too much an occasion of vainglory--but they are what can train our spoiled minds and intentionality. They are the little acts that tone our spirit for the greater renunciations, the ones that really matter.
Penance: the old 3, 3, and 3.