Siviero started coaching in Mallorca's youth academy. His team won their group in
2011–12, but were eliminated from the
playoff semi-finals by
CD Lugo. In July 2012, Siviero was appointed at
Real Murcia CF on a one-year contract after turning down a new deal at Baleares. Siviero was back in the third division and Atlético Baleares in January 2015, on a contract that would extend itself by a year should they avoid the drop. He
achieved this, but he and his staff were axed unexpectedly in November due to conflicts with the board. In
2016–17, Siviero managed
Lleida Esportiu. Following a poor start to the season that saw them in a relegation place, he took the
Catalans to eighth place, enough for a
Copa del Rey berth but not for
the playoffs; his deal was not renewed. Siviero joined
Hércules CF of the third tier in July 2017, for one year. He was shown the door on 15 October after nine matches, split equally between wins, draws and losses. On 30 September 2019, after nearly two years out of the game, Siviero returned to the dugout with last-placed
Enosis Neon Paralimni FC of the
Cypriot First Division, his first job outside of Spain. He left the following January and was close to a return to Hércules weeks later, which abruptly collapsed due to a vote of confidence in caretaker manager Antonio Moreno. Remaining in the
Province of Alicante, Siviero signed for
Tercera División club
CF Intercity on 28 December 2020, for the rest of
the season. The side won promotion to the new
Segunda División RFEF with a 1–0
playoff final win over
Elche Ilicitano. After winning promotion as group winners in the
2021–22 season, his contract was renewed. Siviero's Intercity reached the last 32 of the national cup in
2022–23, losing 4–3 at home to Barcelona after
extra time. He was dismissed on 17 April with the team one point above the relegation zone with six games remaining; his final result was a 2–2 home draw with rivals
CF La Nucía after conceding twice in the final six minutes. Siviero returned to Mallorca on 16 June 2023, being appointed at
their reserves in the
Tercera Federación. He achieved promotion at the end of his
debut campaign. ==Managerial statistics==