Start with what time you want to eat at, and work backwards from that for your timings. Right back to when you need to get the turkey out of the fridge to come to room temperature.
When you take out the turkey, it needs to rest for a lot longer than you think. Some chefs say that you rest it for the same length of time as you have cooked it. I go with 1-2 hours, and that seems to work well. So you take it out, put it on the carving dish, cover with foil (ideally, you've been sensible and kept the foil used for the start of roasting before removing to let it crisp up), and cover the foil with a couple of folded over towels. The towels are like a blanket and keep it piping hot, while the foil helps that but also keeps everything else from sticking to the turkey.
The time the turkey is resting is usually plenty of time to cook roast potatoes, all veg, make gravy etc.
Yes to asking others to bring something useful - root veg either already roasted in a serving dish or prepared and in a tub/bag to just pour onto a baking tray; bread sauce; a cold starter or pot of soup; somebody's special brownies or meringues for desert; etc. If that would work in your family. And also consider what are traditions that you all, as a family, want to keep (eg. bread sauce) but are there any you want to drop (eg. only DDad liked sprouts - so do we not do them, or do we still do them but only a small bowl as we know no-one will eat them out of preference), and also are there anythings that you or others would like to do differently (eg. DDad hated trifle so DM never made it, but lots of us like it so we'll have it as part of our desserts; or in my house we love cheese so I will add a cheeseboard before/after dessert)...not rejecting DDad, but giving yourself permission to think about anything you might want to change, or that others might want to change - or you might have dietary requirements to consider.
Do as much prep as you can in advance. We do most of ours on 24th in the afternoon (going back almost 40 years now) - peeling potatoes and leave them soaking in cold water, peeling and chopping the veg (leaving in cold water or in airtight tubs as necessary - parsnips, onions, garlic etc all need to NOT soak), make breadcrumbs for stuffing (we usually completely make the stuffing too), make herbed butter for going under turkey skin before roasting (and leave that out to stay soft!! so much easier to manipulate on 25th), boil giblets for stock (if you can be bothered).....etc. (We also make a bowl of chopped fresh fruit for breakfast, and cookies for Santa, at the same time - but it's nice relaxed family time in our house, and I always have a spare half batch of cookie dough in the freezer from earlier in December in case we only have time/energy to slice and bake rather than start measuring and mixing ingredients).
Lots of people prep a few weeks in advance and freeze items - if you have space, that can be useful.
Can you delegate setting the table to someone? Or do that also the day before?
Also, check NOW what you have in terms of cutlery, crockery, glasses and serving dishes, for the number of people you expect. If you need side plates for starter, will you need the same ones again for cheese/dessert? Soup and dessert both need the same bowls? Had you planned on 1 serving dish of each item on the table or 2 smaller dishes to pass around both ends of the table - and have you enough for all the things you want to serve? Will you need both roast and mashed potato, or just 1 type? Even if you do 2 bowls for most things including veg, you might only want 1 for sprouts or red cabbage, depending on family likes and traditions. Do you have enough jugs (and will they need to hold gravy first before cream for dessert or milk for tea/coffee)? Do you want both red and white wine glasses, and water glasses, and how many DCs need plastic or less fancy ware? (Will you use wine glasses from the table for pre-dinner drinks also, and do you also need bowls for crisps/nuts at that stage)?
Once you've done that, who can you borrow from - especially those who can bring them over the day before?! Or would they be useful enough to think about buying extras? (If yes, go out and organise that soon, not leaving it to Christmas week!).
Do you have a dishwasher to run a wash say after starter - so you have those dishes again after main course is finished? Or would it mean someone washing up at the sink?
(Have you enough chairs, and a large enough table? Can others bring chairs, does someone have a folding table you can use? Would it work having everyone at 1 long table of a few stuck together, or do you need to have tables scattered in different areas/rooms? Do DCs usually sit with you or is there normally a separate DCs table, and do you want that to change or stay the same? And when you think about these, also think about people getting up and down for bathroom breaks, serving and clearing courses, moving hot food around etc - will there be space when chairs are occupied or will some people be stuck in their seats until the meal is finished?)
Apart from other things, I try to have a sink full of hot water while I cook, especially as we get into the main bulk of things getting finished and put into serving dishes to stay warm, so pots etc are finished with. Having a bowl of hot water already means I can turn around and dunk a pot in there, or even wash it quickly, once I'm finished with it. There are usually a few quiet points that I can sort out the buildup of washing up - and I ask someone to come and dry them intermittantly. I also try and run the dishwasher after breakfast, so it is empty as I start the main meal and those clearing the table after starter/main etc can put the dishes straight into it, saving my worksurface for other purposes. I also try to start the day with all the bins empty (rubbish, recycling, compost), and have useful things like plenty of teatowels, rubber gloves, washup liquid, spare bin bags and kitchen towel etc all easily accessible. And spare apron, oven gloves etc.
It might be useful to have designated people in advance to be in charge of various jobs - taking coats of guests on arrival and knowing where they go; serving pre-dinner drinks and snacks; minding and playing with smaller DCs; doing washing up or drying to assist in the kitchen; keeping chef's glass topped up (whether water, sugary fizzy drink or something alcoholic) as needed; and also any sous-chef assistants that YOU WANT (who will HELP and not get under your feet) or who are just designated company for you to "sit there and chat with our drinks" (and not get under your feet).
One final thing - once you have served main course (or dessert if you really must), you as chef are off duty. Others have the job of pouring you a wine and clearing away afterwards.