Best Answer - Chosen by VotingI think the best way to transliterate your name would be as "카라 사샤나". Transliteration means that this is a Korean approximation of the sound of your name, not the meaning. In Korean, you could translate your name by meaning or transliterate your name by sound. In Chinese you almost always go by meaning, but I think it's fairly common just to go by the sound in Korean (My name is 토니, which is just "To-nee" in Korean)
I think if you told Koreans your name was 카라, then they would remember this, as 카라 is the name of a girl's group in Korea right now.
Perhaps Hailey could help you with creating a 'meaning-based' named. Kara should originally mean "Joy", and Sashanna I think is a form of the Russian 'Sasha' which comes from the diminutive of "Alexandra" meaning "protector of man". So it might be better just to translate the "Joy" part.
Hope this helps!