He attended St. Bonaventure and after his sophomore year he served as a Student Manager under Coach Mark Schmidt. After graduating from St. Bonaventure, he remained in Olean as a Graduate Assistant for the Bonnies. Coach Gallager accepted an Assistant Coach position under Coach Chad Myers at Massanutten Military Academy in Virginia. He helped the Post Graduate team go 32-3 including an appearance at the National Prep Tournament Final Four, the team had a number of Division I players including future NBA player Dereon Seabron (New Orleans Pelicans).

Gallager reunited with Coach Chad Myers at IMG Academy where he again served as his Assistant Coach, the following season he landed a Special Assistant position at Southern Utah under Coach Todd Simon. The Thunderbirds went 24-13, including an appearance in the CBI Semifinals. Simon was named the Head Coach at Bowling Green and hired him to serve as an Assistant Coach for the Falcons.