How you prepare hives for winter depends on where you live. I was reading an article on how easy keeping top bar hives was the other day, and the lady stated that living in southern California, she had to do nothing for fall, and the bees had some nectar flow all through the winter. No wonder she thought it was easy. In the Northwest, losses are still around 30% on average.
While Boise has no where near the cold climate that some folks have to the north of us, there are things that seem to give you an edge when it comes to over wintering hives in the cold. As soon as you harvest honey(preferably no later then August 1st), check the brood boxes for weight, and if a hive with 2 brood boxes, with top and bottom board does not weigh 90 lbs, feed 2:1 sugar syrup until they do, or they go into cluster in fall. Save back a half full super or two as emergency feed in spring. Also, make or purchase fondant for when you check them in the first week of February.
Upper ventilation is also important.
Many people drill a hole in the upper super. This helps remove condensation from the hive, and keeps drips from falling from the inner lid onto the bees.
I prefer to provide ventilation via a slit in the front of the inner cover, so that I don’t have to remember to bring corks when moving hives in summer, but as long as there is good ventilation in the hive, it does not matter how you do it. Many people put in the plastic slider on the screened bottom board. I prefer the bottom open. That is not to say they are wrong and I am right, just that I have not noticed any more dead hives when I do. I can assure you that around here, if you have solid bottoms, entrance reducers, and no upper ventilation, in spring, you will most likely see mold in the hive, and dead bees with it.
Some folks wrap hives, and some do not. If I were in a colder climate with abundant snow and wind I sure would. Whatever keeps you from worrying.
I can tell you this: Bees with adequate food stores, and good ventilation that go into winter with low mite loads and are disease free have the best odds of survival.