When I hosted...I never woke up early because I didn't serve Thanksgiving dinner until a "normal" dinner time...5:00pm.
i would do all the baking on Tuesday. Assemble all casseroles and as many side dishes as possible on Wednesday. I had a separate roaster for the turkey...so they would be cooking in the garage on Thursday leaving my oven and stove top free to cook all the sides and make the mashed potatoes and gravy from scratch that day. It was really easy.
oh...and on Thanksgiving morning I would make Belgian Waffles for DH and the kids. After that was cleaned up I would start my cooking for the holiday.
Both. I do everything that is possible to do ahead of time and then do wake up early (730am for 4pm early dinner) and place the meat in the roaster if roasting anything. I go back to bed for about an hour to nurse and cuddle my LO (he is almost 5mo old) and once he is sleeping is up and lets get this ready.
It's been a while since I've hosted a gathering but in our family everyone brings something to the dinner so I didn't need to be up early prepping/cooking. I've never had to do the turkey~ my mom or cousin always cooked it.
I started making little things like graham crackers and ginger snaps for crumbs for the crust of my cheesecakes and other prep ingredients last week. I made my rolls on Monday and froze them...I made most of the dinner on Wed and the remaining stuff Thursday am....I got up at 6 ish, but that is because it is my norm, there was no rush at all. I didnt even have to get the turkey in until 11.