Hardly ever, even though I was advised when I bought it a few months ago to shut down everyday. I do crazy things like get up in the middle of the night and play games, so I nearly always just put it in sleep mode.
I never power...anything off lol. The only time anything gets shut down is my chromebook(when I HAVE TO), my desktop (When the power goes out), and my phone( when I have to update the rom. ^_^
I kind of do both equally.
I've never been quite sure if turning a computer on/off often ruins it or, if leaving it on indefinitely ruins it so I just do both.