We had random inspections in assembly to check that
(a) our socks were exactly the correct shade of grey ; and
(b) each sock had an embroidered name tag sewn into the top of it.
Anyone whose socks did not meet the precise requirements risked being sent home with a letter suggesting that, if the boy's parents couldn't ensure that the school's rules were adhered to, they should seek an alernative school for their son's education.
Being seen by a prefect, while on your way home from school, without a properly fastened tie and (most importantly) a school cap perched on top of your head was regarded as an extremely serious offence. (However it was nowhere as serious as being seen holding hands with a girl from the school next door; the punishment for that was immediate expulsion!).
I was actually quite annoyed when, just as I got to the sixth form, the rules were relaxed for 6th formers, allowing us to wear sports jackets of our own choosing. I'd been looking forward to having the red cuffs of a school prefect on my uniform blazer!
Here's the current uniform policy of my old school:
http://www.northgate.suffolk.sch.uk/nh/school_information/school_uniform
The school I taught at (in Sheffield) during the 70s and 80s was proud that it had abandoned school uniform. It's now got one!