to do sth as well as you can in order to show other people how good you are :
She didn't do herself justice in the exam.
to do sth as well as you can in order to show other people how good you are :
She didn't do herself justice in the exam.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005