sorry, but you can't write your name in kanji. (you could in chinese, but who wants to do that?) you have to use the not-so-elegant katakana, which will be a phonetic equivalent of your name.
i'm not sure how to pronounce italian... ciro... in japanese it could be kiro(キロ)? shiro(シロ)? suiro(スイロ)? whatever sounds the most like it.