Hey, cool, my name's Karl too, and I also learn Japanese so when I write it I always put かある or in katakana カール. It depends what you thinks best though- just try experimenting with it or something.
Also, in Japan, They tend to say their last names for introduction so I would say わたしははんくすです, in Romaji that's 'watashi WA hankusu desu', because my last name's Hanks.
The name 'Karl' in Japanese isカール (kaaru).
Karl Hennig has written: '\\' -- subject- s -: History, Japanese Gardens, Social life and customs
Karl Adolf Florenz has written: 'Geschichte der japanischen Litteratur' -- subject(s): History and criticism, Japanese literature 'Japanische Dichtungen' -- subject(s): Japanese poetry, Translations into German
Karl Kengelbacher has written: 'Si ge yue de zhan zheng' -- subject(s): Chronology, Sino-Japanese War, 1937-1945, Campaigns, History
Some translations of "Carlos" in different languages are: Spanish: Carlos Italian: Carlo Portuguese: Carlos French: Charles
Karl Fettweis has written: 'Karl Fettweis'
Karl Ghattas has written: 'Karl Ghattas'
Karl marx
Karl Marx Karl marx
Karl benz parents always called him Karl Friedrich
Karl Brix has written: 'Karl Schmidt-Rottluff'
Karl Wild has written: 'Karl Theodor Welcker'