8. "So...does anybody know if Alex is out tonight?"
By this point you'll all be fairly smashed. All tact and subtlety will be gone, while confidence will be high - a disastrous combination. You'd been plotting to keep your latest crush a secret, keeping a sneaky eye out for them later in the night. Well that masterplan just went completely out the window. Your question will be greeted with a raucous round of "OOOOOH"s, and everybody will be sure to tell your poor target exactly what you said about them once you all meet up in town. Good luck bouncing back from that.
7. You'll Try To Mix Your Own Drinks. It Won't Go To Plan.
Sometime during the final hour of pre-drinks the group will become bored of their own alcohol. Don't worry though, you've suddenly all realised you're expert mixologists! The rule of thumb here is to chuck everything in and see what happens; look at those mental colours! The second rule of thumb is never to volunteer to try it first. In fact, unless you've recently acquired a taste for industrial paint-stripper, don't drink it at all. Pour it straight down the sink and remember to call the plumber tomorrow.