Having had an extended career at reserve team level, Slade entered professional sports coaching with Notts County in 1993. He briefly took charge of the club as caretaker manager during the 1994–95 season. Slade then had spells in charge of non-league sides Armitage and Leicester United before joining the coaching staff of Sheffield United in 1997. He had two spells as caretaker manager of The Blades in 1998 and 1999 before the appointment of Neil Warnock. In 2001, he took over the managerial post at Conference National side Scarborough before later moving to Grimsby Town in 2004 and Yeovil Town in 2006. He was appointed manager of Brighton & Hove Albion in 2009 but the stay was brief and he was dismissed in November 2009.