How do you cover up a fart in public?

Ethically, u can't cover up for something that has happened accidentally. People will respect you if you apologise to those that you want to cover up and i bet, u wont live a life of covering up on your bad habits. Its noble and wise to stand up for your wrongs as you correct them that being a coward.

You can't, just apologize.

Scream fire.
You may get a substantial fine, but nobody will ever remember you farting.