If you treat convention with disdain, are you flouting or flaunting the rules?
How to Remember It:
Think of whistling or actually, playing the flute instead of doing what's expected.
Why? Because flout probably originates in the Middle English word flouten, "to play the flute." It's not clear how a word for playing the flute evolved into a synonym of mock and insult (the original meaning of flout), but here's a guess: in the hands of some entertainers, the flute can project a teasing, even mocking, carefree air.
By the way, using flaunt in sentences like the one above is now standard, although many folks still consider it incorrect.