I always turn the downstairs into a bit of a wonderland. We go for a homemade theme usually. Lots of paper chains, strings of popcorn, dried oranges with cloves, cinnamon etc. I've got bunting I made from Christmas fabric. Lots and lots and lots of snow globes (I collect them) with lights near them so the light reflects. We make paper snowflakes and lanterns.
One of my favourite things requires a bit of timing. I start hyacinths off so they bloom throughout December. I have lots of glass hyacinth vases in various colours. I put them on the dining table, coffee table and side tables with candles between/next to them and the light is beautiful bouncing off the vases and they smell incredible.
I go and collect foliage to make garlands to go on the fireplace and on top of bookcases, as well as a few wreaths. DD collects fir cones and spray paints them, as well as twigs and makes pom poms from wool and creates some quite striking decorations with them.
Our Nativity was knitted by my Grandma many years ago. We also have a couple of big wicker hamper baskets in the corner of the snug and dining room, next to the armchairs and they're filled with Christmas books and have a pile of festive cushions and throws next to them.
We also have some vintage Chinese paper lantern decorations, vintage Christmas tins and we replace the crockery with my Christmas Spode and all the mugs are swapped out too.
Lots of other things too. I adore doing it and the children are counting down to December 1st.