We don't like leaving key bits of food shopping until right before in case we can't get them for any reason, so the turkey crown, pigs in blankets and stuffing are all bought in advance and frozen.
Post it notes on the fridge with reminders to take things out of the freezer on time.
I buy the gravy rather than make it.
We don't go overboard with buying presents, and get DD some second hand things through the autumn/early winter if I come across something great.
Put all Christmas decorations away in clearly labelled boxes so everything's easy to find, and write reminder notes on the box for myself/DH for next year about anything that'll need changing (e.g. the tree lights have given up the ghost after ten years and need replacing, we've used up all the crackers, etc)
Make sure all house cleaning/washing up and laundry are sorted before the day so we're not having to find and wash the potato peeler/sieve/Christmas jumper/whatever.
Leave notes for myself directly in my eye line on the kitchen cupboards when cooking the main meal. This year's were "The pigs in blankets take longer than you think,", "Don't forget to take the foil off the turkey,", "Put the fat for the Yorkshires in EARLY!" and so on.
Make sure there's room in the recycling bin.
Build in a prearranged time to FaceTime my parents so they can see DD.
Basically, it just requires me to be far more organised than I usually am!