When it is too cold to swim and time to winterize an above ground pool, this is what I do. I top off the water and cover the pool with my winter cover. For the rest of the winter it is just a once a week thing to pull the cover back a little, add some chlorine and run my filter in the circulate mode for a few hours. Once the outdoor temperature cools down, that's about all the maintenance an above ground pool needs.
Keep in mind I live in Arizona. In the valley of the sun. To winterize a pool in colder climates you have just a few more concerns. Here are some tips for the colder climates. Install your skimmer guard, drain and plug the skimmer. You should also unhook your filter equipment and store in a save place for the winter. It's also helpful to use floats under your pool cover to keep some of the rain water out of your pool.
By keeping the water out of the skimmer you eliminate the risk of the water freezing and cracking the skimmer, or possible kinking the wall under the skimmer in case of water loss.
Keeping your cover free of water, leafs and other debris is helpful in keeping your cover in good shape for use year after year.
The nice thing about vinyl lined pools is that they require so little maintenance during the winter. The vinyl, being non porous, requires much less upkeep than an in ground pool. Allow for an early start in the spring to top off the water, do some vacuuming and stabilize your chlorine and you will be swimming when the weather permits.