Deciding when to start your end of year yard work is a delicate decision: too early and likely you'll have to keep reworking until the snow comes, too late and your yard will be a mess come spring. Or you can take my father's route which seemed to be just working on it all the time. The best path however would be to listen to the advice of professional landscapers about how they prepare their personal lawns for winter.
The most surprising thing I found on this list was the idea that one should water their evergreens (depending on your precipitation levels) to keep them from dehydrating in the winter. Also, you should keep cutting your lawn all the way through November if you can; uncut grass shades the lower pieces and prevents growth, and then the taller grass has a higher likelihood of lying down beneath the snow and creating snow mold (which nobody wants).