I don't know if anyone is still following this thread, but i'll throw my two cents in...
First, I start watching Christmas movies. (Tonight, I already started with my wife! We watched Prancer and I just finished watching The Polar Express.)
I have A LOT of Xmas movies I enjoy! My favorites are:
Home Alone 1 and 2
A Christmas Story
The Night They Saved Christmas
Elf
It's A Wonderful Life
How the Grinch Stole Christmas (both cartoon and full-length movie)
Christmas Comes But Once A Year
Rudolph
Frosty (both versions)
Garfield Christmas
Charlie Brown Christmas
The Santa Clause
A Christmas Carol (all versions!)
California Raisin Christmas
Okay, I could go on forever with those!
Anyway, music is obviously crucial in prepping for the season. I like to start listening to Christmas music about at the time of the first frost of the year. Sometimes sooner... And I'm a little specific about what KIND of Xmas music I play: Classics! Home Alone soundtracks. Instrumentals (from orchestral to piano solo to celtic/folk to trans-siberian). Old Times (think Time-Life Treasury of Christmas)... Basically anything that's not ruined by so many current popular artists (unless they become classic, ie, "the Christmas Shoes").
All Saint's Day (November 1, for those who don't know when that day is) is the day I start really getting into the spirit. Halloween is over, so forget Thanksgiving decorations (in my opinion, everyday should be a day of thanks), and get straight to CHRISTMAS! Computer wallpaper is usually a scene of a Thomas Kinkade holiday painting. Piano is covered with a hunter-green lace and red and green garland and this year, two old-fashioned lanterns with a cozy electric candle light in each, set on both sides of the top of the piano. Along with a 16"-standing doll of Father Time.
And that's just getting things started... !!!