do a mischief



do yourself a mischief

  (British & Australian humorous)
if you tell someone they will do themselves a mischief if they do something, you mean they will hurt themselves You want to be careful jumping over spikes like that - you might do yourself a mischief!
See also: mischief

Common Names:

NameGenderPronouncedUsage
Yekaterinaye-kah-tye-REE-nah, ee-kah-tee-REE-nahRussian
Vasilica-Romanian
Ballester['bælistə]
Alicjaah-LEETS-yahPolish
Charis['tʃæris]
Radovan-Slovak, Czech, Serbian, Croatian, Medieval Slavic