1
general::
Phrase(s): live it up
to have an exciting time; to do what one pleases—regardless of cost—to please oneself. • At the party, John was really living it up. • Come on! Have fun! Live it up!
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Enjoy oneself, often extravagantly. For example, They came into some money and decided to live it up with a trip around the world. [Colloquial; mid-1900s]
American Heritage Idioms