Differences in Artists.
A self taught artist has not received any training from professional people, they have probably from a young age loved to sing and so over they years they've experiemented...
Leonardo Davinci was not trained he just had the talent but you might want to know he had may jobs. before being a artist he was a priest and gave his money and clothes to poor people.
If I'm reading your question correctly, it's an artist who designs the tattoo without tattooing the design on someone. They create the image while someone else does the needlework for it.