Ooh let's go! I live for making Christmas Dinner, it's actually my favourite thing to do, I wrote a post last year explaining I used to make dinner for the girls I worked with and their kiddos (loads of single mums working in a nursing home, basically I'd have the kids dropped to me of a morning and the girls would cover my shift, I'd do the kiddos a festive breakfast and crack on with getting dinner sorted for years! Sometimes if there was a grandma who would be alone then they'd come over and help me with all the kids, it was like a ww2 christmas scene 😂) so loads of different dishes is your friend here, because you can make it look really special but without loads of mess. This is my suggestions and if you have a tight budget it's great to make from scratch when the veggies all go cheap and all the dishes are easy to do.
If you don't have a slow cooker or a air fryer someone will so get borrowing! I'll leave you some recipes if you want, just @ me and I'll dig them out for you.
The turkey needs as long to rest as it does to cook, cover it in tinfoil tightly and stick tea towels over it, that will keep the heat and the bird retains juices.
If you have an air fryer it will be invaluable for pigs in blankets.
You can pre make vegetable mash and normal mash, I add truffle cheese (aldi does a cheddar truffle cheese and sainsburys do also) and they freeze well but I add mine to foil trays once they're made and cover in foil (foil in all it's forms will be your buddy here and they can sit bottom of the oven on a baking tray to heat through when things are cooking.
Roasties you can either cook the night before or just peel and parboil, however I tend to make loads of roasties cooked in goosefat and once cooked drain most of the fat, but not all if reheating, so they get a thin layer of fat form around the spud but once reheated crisps up. They also reheat tremendously and quickly in the air fryer.
Slow cooker - braised red cabbage with a nice sharp apple sliced up, red onion and christmas spices.
Foil trays - honey and mustard parsnips and carrots again can be reheated if you just roast the day prior and add honey and mustard on the actual day to reheat so honey doesn't burn.
I do sprouts with pancetta and chestnuts in my wok, again I make the day before and just heat up on the wok.
Stuffing, I cheat and buy the fancy packs (2 for £3 in tesco) and add sausage meat so I have 2 different kinds, I make stuffing balls and add slices of apple or a few cranberries on top and rosemary or thyme sprigs to look festive. I tried making a stuffing wreath but I look a bit shit so I stick with parcels/balls.
A cauliflower cheese/vegetable gratin in a foil tray, don't boil cauliflower or brocoli or leeks, roast a day earlier in a small amount of oil and seasoning, (s&p or maggi liquid seasoning is game changing!) And then pour over your cheese sauce, again that will last in fridge for days and can be heated up and coveted in foil for ages with the tea towel trick.
For 12 people and because the foil trays can all be piled up on one another in the oven the days prior to Xmas day I'd consider making a dauphinous tattys, so impressive and so easy to make. I make mine in a pan, leave it overnight in the fridge so it's not too liquidy and reheat in pan, bung under grill with brie or gryre and again, wrap tightly in foil and just let the over keep everything hot.
Gravy I use Jamie Olivers chicken wing gravy recipe, make more than you think you'll need and have it in a pan on stove top (because everything is being kept warm in oven your stove top is mostly free for gravy and bread sauce) and add those glorious turkey juices from its rest and reduce it until it tastes amazing!)
I think sprouts in wok, gravy and bread sauce are the only things I use my hob for but if someone fussy wants plain boiled veg I have a spare ring free on the hob)
If you make Yorkshire puds (I have a recipe for that should you want it!) I do mine Xmas eve and just reheat them when I'm unwrapping my endless foil trays, I carve the turkey before this and the pigs in blankets and stuffing are all being kept warm by more foil and teatowels.
Starters you want something easy but I don't do a starter, I do nowadays a festive looking charcuterie board for people to graze on until the main meal.
I make a Christmas cake months in advance, have mince pies and a shop bought Xmas pudding and brandy cream in and a chocolate yule log with cream for the kids. Nothing remotely strenuous for pud.
I used to make my own cranberry and apple and mint sauces but it's cheaper and nicer to buy shop bought (not as poncetastic though)
But foil trays, tea towels and preparation will make it so much easier and the more dishes you make that just need warming through the easier it is.
I get lots of cans of coke and kids drinks and keep the booze in the garden to keep cold and keep kids from under my feet.
Also if you're doing breakfast for the day just buy pastries and give everyone butter, jam and Nutella with some bucks fizz and coffee or, if you feel fancy hot chocolate with baileys for adults and some cream with a chocolate coin on top and candy cane for the kids. We don't drink so we have entirely booze free Christmas for us but I get in amaretto and aldi baileys and bucks fizz for guests. If they bring beer etc that needs chilling it goes in the garden and keeps out my way.