I always wake up on December 26th with an eagerness for some austerity. I can easily overdo it on Christmas. I always go overboard on the food, decorations, and gifts.
During this last week of the year, as you begin thinking about goals and resolutions, consider mixing some form of self-denial into them. Yes, self-discipline is typically inherent in most resolutions, but I think an extra touch of the ascetic can be good for the soul. And perhaps necessary after a month-long merriment of excess.