I’ve never done a holiday meal (Thanksgiving or Christmas) that has been more than 4 people, and haven’t done one since my mother passed away in 2019. Even so, things can pile up quickly if you don’t have some form of a schedule. So even if I’m making a turkey breast for myself the Saturday after Thanksgiving (which I did after spending 2019 T’giving at my sister’s in-laws), I still have in my mind the timing needed for everything to come together at the same time.
The pie (apple and/or pumpkin) are done the day before. No ifs, ands, or buts.
I usually work backwards from when the turkey needs to come out of the oven while sits for its 20-30 minute resting time. If dinner is supposed to be served at 3:30, the bird goes in so it’s ready to come out by 2:45 or 3 at the latest. Then again, it’s the LindaWhit family tradition that if dinner is said to be at 3:30, it’s actually served at 3:45 or 4:00 p.m. 
I’ve already pulled out butter, milk/heavy cream, and sour cream out about a half hour before their needed for the mashed potatoes so they come to room temp. A jar is already prepped with flour, s/p, and other seasonings so I can add cool water, shake it up, and whisk it into the pan drippings and chicken stock in the roasting pan when I need to make gravy (this is the last thing I do).
While the bird rests, potatoes get mashed (as they’ve already been put on to boil and drain just after the turkey comes out), I’m already doing the last cook on the glazed carrots, green beans go ON the back of the stove to steam during the last 5 minutes, slivered almonds are toasting in the convection toaster oven, gravy pitcher and serving dishes are heated with extra-hot water before being drained, wiped dry, and veg is put in them, covered and brought to the table, wine cork gets popped (if I’m not already enjoying a glass during prep…oh, who the hell am I kidding - of COURSE I’m enjoying a glass of wine during prep!
) Turkey is carved and plattered, while gravy gets made from drippings and chicken stock (after using a fat separator to keep the good stuff from the drippings), then poured in to the pre-heated pitcher.
It’s a dance that comes with practice, I think. I used to marvel at how Mom got it all done - and then she showed me the ropes (and roped me into making the pies the day before!)