Basic etiquette for staying on a friends sofa after a night out.
  1. Don't sleep naked
    No one wants to be greeted with your naked butthole in their living room on their hangover.
  2. Do help yourself to a glass of water
    Morning you will thank you for your foresight.
  3. Don't be sick on the sofa
    Because a) you'll have to sleep in it and b) a quick dash to the loo to loudly vom is preferable for your friend than having their living room smell of chund for a fortnight after.
  4. Do thank your host
    You owe them - a drink out, a bottle of wine or most likely: a bed for the night when they need one.
  5. Don't leave a mess
    Leave it like you found it. If you don't know what it looked like, just make it look like someone's mum is coming round. Not necessarily your mum, but someone's.
  6. Do leave quickly and quietly
    Overstaying your welcome by digging in and ordering a pizza is probably only acceptable either pre arranged or with closest friends. And their housemates might not like it. Best to get out as soon as you're able and get to your own mess.