Keeping gravy warm in a thermos! Why didn’t I think of that???
Make your pies and freeze them unbaked.
For a fruit pie, you can make the whole pie then freeze it unbaked. Then on the day before Thanksgiving take it out of the freezer and "expect to bake a whole [frozen] pie for 20-45 minutes more than the recipe specifies, depending on the temperature of your freezer and the amount of filling," advises Anjali Prasertong on The Kitchn. (Directions here). For single crust custard pies like pumpkin or pecan, make the bottom crust, put it in the pie dish, wrap and freeze, then fill and bake the day before Thanksgiving. (Directions here from Martha Stewart).
Get your knives professionally sharpened.
Because cooking is easier and more fun when your knives are SHARP.