know which side bread is buttered on

know which side (one's) bread is buttered (on)

To know how to best ensure one's success. I know which side my bread is buttered on, so I was very nice to the recruiter and promptly sent her a thank you card after our interview.
See also: bread, butter, know, side
Farlex Dictionary of Idioms.

know which side one's bread is buttered on

Prov. to be aware of where your money comes from; to be loyal to the person or thing that will benefit you the most. Wife: Please be sure not to upset Grandma. You know we can't do without the money she sends us every month. Husband: Don't worry. I know which side my bread is buttered on.
See also: bread, butter, know, on, side
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • know on which side your bread is buttered
  • know which side (one's) bread is buttered (on)
  • as we know it
  • I know
  • before you know where you are
  • by any chance
  • AFAIK
  • a closed book
  • closed book, a
  • before you know it