He started his coaching career at Preston and became first-team coach. He joined Billy Davies as first-team coach at Derby County in 2006.
In January 2009 he again joined up with Billy Davies when he was appointed first team coach at Nottingham Forest.[3] He left in June 2011 following the departure of Billy Davies from the club and the appointment of his successor Steve McLaren.[4]
In 2012, he returned to Bolton as U16 coach at the club's youth academy[5] he assisted Jimmy Phillips during his brief stint as Caretaker Manager following Owen Coyle's sacking in October 2012.
On 7 February 2013, he returned to Nottingham Forest as first team coach to Billy Davies. Darby left the club after Fawaz Al-Hasawi brought an end to Davies' reign as Manager at the club on 24 March 2014. On 20 November 2014, Darby settled with Forest out of court over an unpaid bonus case.[6]
On 2 July 2015, it was announced that Darby had joined Uwe Rosler's backroom staff at Leeds United as first team coach.[7]
In August 2017, it was confirmed that Darby had taken on a full-time role at the Bolton Wanderers academy, having spent the previous season coaching the U-16 team.[8]
Upon the departure of Keith Hill as Bolton manager in the summer of 2020, Darby reverted to his old role with the club's academy.[9] In May 2022, he was promoted from U16's Manager to U18's Manager.[10]