I ususally clean my stuff and start to replenish the stocks. I'll get a couple dozen boxes of Pro V1x, couple dozen gloves, grab some new hats giving away my old ones and usually grab some more pants, shorts and shirts for the season. Shoes are always taken care of so that isn't part of the routine.
I never really stop playing even though I live in Nebraska. Winters here blow but fortunately we have a nice indoor place to hit balls, putt and work on the short game. I also have a fairly large putting green in my basement with 5 holes in it so when I can't make it there, I at least work on my stroke at home.
Other than restocking the supplies, I don't do much but practice and go "MyJoysing".