To do this you should treat the day like it’s just an average day. Activities such as meeting up with friends and doing something (NOT shopping as you may accidentally purchase something someone has already got for you. ) or walking/running, swimming or even staying at home and doing homework, cleaning your room will keep your mind off Christmas and on the task at hand so you don’t feel super christmassy.
Pretend that you have to wake up when your parents wake up, so you want to fall asleep and sleep in. If you are up hours, or even just an hour before you are allowed to wake up your parents/open presents it will feel like a lot longer as you are waiting in suspense, so keep yourself (quietly) occupied. If you wake up and can’t get back to sleep then do a quiet activity that doesn’t involve electronics (ie reading, writing, tidying your room).
If you have to wait until everybody’s up to do stockings then follow the suggestions in the previous step to keep yourself occupied. By now other excited siblings (if you have siblings) are probably starting to wake up as well. Tell them that you can’t wake your parents up yet and suggest things to do such as: make the family breakfast (if you are allowed to use the toaster, jug etc. ), play a board game, play video games together (quietly!)
If parents/guests/pets/siblings are sleeping refrain from things such as TV, talking on the phone and anything noisy as you may wake sleeping people.