I knew it was time, when I only shaved my head in the summers from 2006 to 2009. Every winter I would let my hair grow back, it was less and less on top of my head. In April 2010, I went and had all of my hair clippered off with no guard, by my wife's beautician and since kept it shaven. Usually by this time of the year I would let my hair grow back. This year is different. I am still shaving it.