Do your veg prep the night before and store in water where possible.
Consider buying a 3 tier steamer so you can cook several vegetable dishes all on one hob.
A pressure or miulticooker can cook most things in 8-10 minutes if you're short of time.
Save on washing up by using disposable tin foil trays and dishes. You can rinse and recycle at the end.
Check you have enough tin foil in the house! You'll need a LOT to enclose a turkey, so I usually buy more than I think I'll need.
Make some dishes ahead: You could cook stuffing now and freeze until you need it for the big day.If you wanted, you could cook all your veg in advance and do the same, but it's likely to go a bit mushy.
Some frozen foods, like Aunt Bessie's roast potatoes and Yorkshire puddings are a great helping hand and still taste homemade.
Add some stock cubes, herbs and or even some double cream to instant gravy if you're short of time for a richer taste.
Don't buy your meat last minute as I found it doubles in price on Christmas week. Also, buying a frozen packaged joint conveniently has cooking times to follow whereas our turkey needed longer than I anticipated.