It depends year to year, but generally, we go cut down a real life Christmas tree (we didn't this year) and haul it home to decorate.
We then venture outside to put lights up around our house. My family do like to do night drives to go Christmas light hunting, but ever since we moved to a neighborhood that has a much older demographic, it is like every 1/2500 houses that have decorations up. So we don't do it as much anymore.
Our two main traditions, is to go shopping late at night at a shopping centre (like at 10.00 -12.00), and to always make a gingerbread house.
My mum and I like to go down and listen to the local christmas carols. Other than that, chirstmas day is just LOTS of driving to go visit relatives. I bake SO much. I bake biscuits, pavlovas, cakes, you name it. We don't really have much of a christmas lunch anymore, as there is just too much going on.