indelible make-up
Using one of those black indelible markers we would get some kid (it worked better on blonde ones) and give him a 'Spanish' or 'Mexican' moustache, glasses, sideburns and, sometimes for good measure, we'd write 'fuck' on one cheek and 'cunt' on the other. If you went over it a couple of times it was almost impossible to erase for days. If the kid already wore glasses a variation was to colour in the lens.
written by Bo* Rog*rs, approved by Log

Indelible make-up is very funny until a particularly waggish group of your school chums pins you down on the cricket field and gives you a full Groucho Marx job just half an hour before your GCSE German oral exam is due to start. Fortunately, you can't fail GCSE German just for turning up to the exam looking like a complete tit.
written by go*don *iot, approved by Phil