There's no direct translation for "love it" in Hawaiian, but you can use phrases like:
* Mahalo nui loa! (Thank you very much! - often used to express appreciation and love)
* Ua maikaʻi! (That's good! - expresses approval and liking)
* He nani! (It's beautiful! - used to show admiration)
These phrases are all appropriate to use when expressing your appreciation or liking for something.