Born in Cabudare, Castillo started working as manager at several local sides in Lara state. He led Fundación Lara Deportiva to a first-ever promotion to the Segunda División in 2019, after winning the Tercera División promotion play-offs. After being in charge of the side during the 2020 and 2021 seasons (as the club was named Academia Rey), the side confirmed his departure on 24 March 2022.
