What do you like and dislike about other peoples' hosting? Do you like drinks and nibbly bits before dinner?
Dinner before the Queens Speech?
I like to do all the cooking ( I have a kitchen/dining room/sitting room "L" shaped ) , I have a "Non Players Off the Green" rule 
DD sets the table but other offers of help are waved off. Guests can chat to me but only from their seats .
DH helps to put the dishes on the table and makes sure everyone has drinks.
My DParents wouldn't cope with decorations on the table. I have candles (usually floating in a glass bowl) and table gift sweets. Not too much to move about.
Do you have enough plates/Glasses/Cutlery/Gravy boat/cruet set/table dishes for the veg and sides/sauce/ serving spoons/knife to carve ....I didn't have a carving knife but I am a lentil weaver.
A tin for the turkey if you're having this.
Table cover and napkins
Nice plate for your mince pies and the cake.
Look in Homesense/TKMaxx , they are brilliant
Get a big plastic bin (new) to chill drinks , fill with ice+water (if you want to keep your labels wrap the bottle in clingfilm) . I put ours in the porch which is cold.
You'll need all your fridgespace (you do know you need a Christmas Fridge Experience
)
I know people recommend foil trays to save washing up but I don't feel they cook as well (we don't eat meat so I only cook turkey for guests)
Clear spaces in the kitchen worktops, have an empty bin and fill the sink with soapy water .
Lists are your friend !