Still was born in 1904 in Grandin, North Dakota and spent his childhood in Spokane, Washington and Bow Island in southern Alberta, Canada. In 1925 he visited New York, briefly studying at the Art Students League. He attended Spokane University from 1926 to 1927 and returned in 1931 with a fellowship, graduating in 1933. That fall, he became a teaching fellow, then faculty member at Washington State College (now Washington State University), where he obtained his Master of Fine Arts degree in 1935 and taught until 1941. He spent the summers of 1934 and 1935 at the Trask Foundation (now Yaddo) in Saratoga Springs, New York.