to save your life

couldn't (do something) to save (one's) life

slang Cannot do something well or at all. Ugh, this art assignment is so annoying—I couldn't draw an apple to save my life. Rachel is so selfish! She couldn't consider another person's feelings to save her life.
See also: life, save

to save (one's) life

Regardless of one's effort, passion, or desire. Ugh, this art assignment is so annoying—I can't draw an apple to save my life. Rachel is so selfish! It's like she couldn't consider another person's feelings to save her life.
See also: life, save

to save your life

used in various expressions, especially can't (or couldn't ) do something to save your life , to indicate that the person in question is very incompetent at doing something.
The first recorded use of this expression is by Anthony Trollope in The Kellys and O'Kellys ( 1848 ): ‘If it was to save my life and theirs, I can't get up small talk for the rector and his curate’.
See also: life, save
References in classic literature ?
Take my advice, therefore, and if you wish to save your life follow some other path.