Schaefer was born in the East Prussian town of Pillau, Germany (now Baltiysk, Russia), near Königsberg (now Kaliningrad).
[1] Schaefer was a milkman, a job that required him to deliver fresh milk to households in the suburbs every morning, and to which his extraordinary physical fitness was often attributed.
[2] Schaefer started his football career in 1960 with Blacktown in west Sydney, playing in the second division of New South Wales.
He then coached Sydney Olympic in the national championship from 1982 to 1986, where he was twice runner-up; Brunswick Juventus in the state league of Victoria in 1988; APIA Leichhardt from 1989 to 1991; Sydney United from 1992 to 1994; Leichhardt Tigers in 1995; Marconi Fairfield from 1995 until 1997, leading the team into the grand final of the national championship against the Melbourne Knights FC, where they lost 2–1; Adelaide Sharks from 1998 to 1999; and Parramatta Power from 2002 to 2004, where he served as assistant coach, and was runner-up in the national championship of 2004.
His daughter Kim Schaefer played a couple of non-A international matches for the Australia women's national soccer team.