She then studied formally at the Ontario College of Art in Toronto (1927–29), where she was taught by portraitist John Alfsen and Group of Seven landscape artists Arthur Lismer, Frank Johnston, and J.E.H.

In the summer of 1946, while working at the Banff School of Fine Arts, Nicoll met Jock Macdonald, a fellow faculty member.

[4] Becoming the sole artist in Alberta to work in automatism, Nicoll frequently produced paintings and drawings without premeditation for the next six years, accumulating four-foot-high stacks of sketchbooks.

[7] Nicoll worked in a diverse range of media, including print-making, ceramics, batiks, jewelry making, and, above all, painting.

[9][10][5] Nicoll had to abandon painting in 1971 due to arthritis, but continued to make art by using a more physically manageable, though unconventional technique she called clayprinting.