Have A Comb And Handkerchief With You
When I was in Junior school (UK boarding school in the ‘80s), we were not allowed to say OK as it was considered slang and not befitting the young ladies and gentlemen that we should aspire to be. For context, Junior school covered ages 5-13.
We also had to have a comb and a handkerchief on us at all times. On top of that, we weren’t allowed to have our hands in our pockets because, ‘it looks slovenly’.