Complex sentence: In the early 1950s he moved to New York to work as a musician, was a professional percussionist until 1960, which became a means to support himself as he focused more on his work as an artist in his studio.
Split into simpler sentences: In the early 1950s he moved to New York to work as a musician. He was a professional percussionist until 1960, after which he used it as a means of support while he focused more on his work as an artist in his studio.