do somebody/yourself a mischief
do (one) a mischief
To do something that harms one. Primarily heard in UK, Australia. You sure did your brother a mischief by including him in that dangerous game.
do (oneself) a mischief
To do something that harms oneself. Primarily heard in UK, Australia. I think you'll do yourself a mischief if you try that risky skateboard trick.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
do yourself a mischiefINFORMAL
If you do yourself a mischief, you injure part of your body. I think I'd do myself a mischief if I tried to copy any of her dance moves.
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012
ˌdo somebody/yourself a ˈmischief(British English, informal or humorous) hurt somebody/yourself: You could do yourself a mischief wearing such tight trousers!
Farlex Partner Idioms Dictionary © Farlex 2017