Muna,
Everything is the same, except that your FC will not get used up very quickly..
As far as testing, you will soon get a "feel" for how your pool works and that will dictate how often you test.
In the winter a salt cell will quit making chlorine when the water gets to about 55 degrees.. When that happens, I start using Liquid Chlorine.. Normally adding it about once a week or so...
Other than that I don't treat my pool any different in the winter than I do in the summer .
Thanks,
Jim R.