He moved to Milwaukee, Wisconsin, in 1914, where he worked for a flour milling firm based in Minneapolis, Minnesota.

He joined the football team at Marquette University in 1916 as an advisory coach under fellow Dartmouth alumnus, John B. McAuliffe.

Ryan replaced McAuliffe as head coach the following year and held the post for five seasons, during which he compiled a record of 28–5–5.

He moved to Northwestern University in 1925, where he was the ends coach for five seasons under Glenn Thistlethwaite and Dick Hanley.

Ryan returned to Hanley's staff as an assistant coach and scout in 1934, and continued on under Pappy Waldorf until 1939.