Recheck your schedules and lists
Make sure you have everything you need. Now's a perfect time to buy those last minute ingredients like produce. If you have a frozen turkey, make sure to take it out now so it can defrost. If you'll be buying a fresh one, get it today or tomorrow (and try brining it for extra flavor and moisture!)
Last minute cleaning and organizing before guests come is also best accomplished now, leaving you time to relax and enjoy company. If you've put off things, focus on the main rooms (kitchen, living room and bathrooms.) Clean off the main horizontal surfaces in each room- this makes the biggest impressions. Floors, counters, table tops, bookcases- organize the contents a bit and then dust. Clean floors last, so you don't have to go back over them.
Take some time for yourself before people come over or you leave. Remember to give thanks and enjoy the holiday season.