After his retirement, Gonias worked as a football commentator for Greek television, while also professionally taking up Golf in Glyfada, Athens. However, he decided to return to professional football as a manager, starting his coaching career in 2013 at Glyfada and afterwards taking over management of Football League side Episkopi. In July 2016, Gonias was appointed manager of fellow 2nd tier club Kallithea, leading them for 8 games with a 2−0−6 record. After an unrealized deal with Gamma Ethniki side Volos NFC, Gonias was appointed manager of newly promoted Football League club Ergotelis in August 2017.
Ergotelis
Gonias' unique approach to the game was met with suspicion from Greek media at first, even more so as the Cretans struggled to earn points on the Table and became relegation contenders at an early stage during the tournament. Despite criticism from local media, as well as a portion of the club's fans, who often demanded Gonias be sacked from his post, Ergotelis' board placed their full trust in their head coach' work. After an experimental First Round, Ergotelis' squad significantly improved and maintained an impressive good form, winning several key matches, scoring many goals, maintaining ball possession rates close to 60%-70% and eventually battling their way out of the relegation zone.
Wadi Degla
Earning credit for Ergotelis' impressive improvement and acclaimed performances, Ergotelis' owner Maged Samy offered Gonias the head coach position at his Egyptian Premier League club Wadi Degla starting from 12 June 2018. On 11 February 2020, Gonias was dismissed from his duties at Wadi Degla.
Tactics
Gonias' teams place much emphasis on retaining possession of the ball and dictating play, often playing a high defensive line with the full backs pushing high up their respective sides. His teams are usually young, and rely heavily on passing and positional interchange to retain possession, a style of play reminiscent of the tiki-taka style of football. As a result, his teams often achieve possession percentages close to 60-70% throughout the game, but are also known to easily concede goals on the counterattack. His unwavering approach to the game regardless of the opponent and match progression, has often been openly questioned by the press and fans as inappropriate for the realities of the second tier of the Greek football league system. Gonias has therefore built a reputation in Greece for his post-match analysis during statements to the press, and his tendency to get overly defensive when questioned about his tactics.
