Following the end of his playing career, Fust started an education at the
Canadian Security Intelligence Service, while working as a volunteer assistant coach of a college team. Fust kicked off his head coaching career at Swiss NLB side
EHC Visp in December 2007. He guided Visp to the NLB finals in 2010 and left the club at the end of the 2009-10 season to take charge of NLA team
SCL Tigers, where he had spent five years as a player. Fust coached the Tigers to a sixth-place finish in the 2010-11 NLA regular season and their first ever trip to the NLA playoffs. He was relieved of his head coaching duties in December 2012 after a series of eight straight losses. He was named assistant coach of NLA side
Lausanne HC for the 2013-14 campaign and opted to leave the team after one year to work for the Swiss ice hockey federation: Fust served as assistant to head coach
Glen Hanlon on the men's national team and took over the head coaching job at the Swiss U20 national team. After Hanlon stepped aside in October 2015, Fust served as interim head coach of the Swiss national team during the 2015
Deutschland-Cup and was then succeeded by
Patrick Fischer. Fust remained in his position at the U20 national team until his contract with the Swiss ice hockey federation ended in 2016. In April 2016, he signed a contract to return to
EHC Visp. He took over the head coaching job at the club. In March 2017, he parted ways with the club after falling to
HC La Chaux-de-Fonds in the NLB quarterfinals. Fust was named head coach of Swiss
National League team
Lausanne HC on February 8, 2018, replacing
Yves Sarault. He stayed on the job until the end of the 2017-18 season and took over the job as head of the youth development at Lausanne in May 2018. Additionally, he was named an assistant coach for the Danish Men's National Team in April 2019. ==Career statistics==