It's been really interesting reading everyone's christmas plans/traditions, so I thought I'd come share mine.
We normally get the tree and put it up about a week before christmas. Every year my mum decides that 'maybe we should just have a small tree this year', cue my sister and I arguing back with her and so she always caves in and we get the biggest, bushiest one we can find that will fit in our lounge. Then we get the christmas boxes down from the loft, decorate the tree and house whilst listening to christmas carols. My sister and I particularly enkoy singing along to the version of rudolph the red nose reindeer we have (it includes all the extra bits, the ones shown in brackets here: http://www.the-north-pole.com/carols/rudolph.html
For the last few years on christmas eve we have been going to my aunt's house (my dad's sister). Normally we go in the evening and my aunt also has some friends and neighbours round. Though this year she isn't inviting everyone around so it's just us going round for a late lunch.
On Christmas day I wake up and open my stocking that's on my door handle then go through and see my sister and we compare stockings. Then we go wake up the parents, though these days they are normally awake before us anyway. We all go downstairs and they make some tea, after which we are allowed in the lounge. The presents are all under the christmas tree and my sister and I pass them out. We then all open our presents at the same time, but quite slowly so everyone gets a chance to see what everyone is getting. At lunch time we go round to my aunt's (mum's sister) house and my other 2 aunt's and families are there (there are 13 of us in total). We then all have presents from each other followed my christmas lunch. Christmas lunch consists of the usual turkey (or veggie alternative for me and my sis), roast and boiled poatatoes, lots of vegetables, gravy, bread sauce etc. We also have starters and pudding. Basically we all end up completely full. Then in the afternoon we all drive down to my parents house and eat more food, watch dr who, play various games and have general fun.
A few days after this we have a big family gathering at another of my aunts house and all of my mum's side of the family normally come (she has 7 sisters and a brother + their partners and kid and kids partners).
This year a few things are going to be slightly different though. One of my aunts and my cousin who we are really close to are actually going to stay over at our house on christmas eve night so that in the morning all 6 of us will have presents together. Which should be loads of fun. We are also having the main christmas lunch at our house and so will probably go for an afternoon walk or something in the afternoon to break up the day a bit and not feel confined to one house all day.
Although I'm 19 and my sisters 23 we still do christmas in our house like we did as kids with quite a lot of presents and still doing stocking etc. I suspect it's not til my sister and I have properly moved out (we're both at uni) that we will actually become mor elike equal adults to our parents and get equal numbers of presents as they do (though they still get each other a lot and we get them both presents).
Typing this all up has made me really excited now.