I saw this link on Facebook and thought about reading it… best decision ever! This is very helpful. It even talks about the etymology of some of the phrases. Good read!
Correct way to say it: I couldn’t care less.
Meaning: If you “could care less,” then you care and are capable of caring less. Make sure to keep it negative — meaning you don’t care and couldn’t care any less.
Click on the title and it will direct you to the site.