Rossley started his coaching career in 1969 at the high school level. After serving as a graduate assistant coach at the University of Arkansas in 1972, Rossley worked as an offensive assistant coach at one high school and several colleges. These coaching jobs were at Lake Worth High School, the University of Cincinnati (his alma mater), Rice University, Holy Cross, and Southern Methodist University, respectively. He also spent time coaching in the Canadian Football League, Arena Football League, and the now defunct United States Football League.