Guy came through the Derby County youth team from the age of nine to turn professional at the club in February 2015. He played all three Group Stage games for the under-23 team in the EFL Trophy during the 2016–17 season. He joined EFL League One club Port Vale on a half-season loan on 11 January 2017. Nine days later he was named as man of the match on his first team debut for Port Vale in a 2–2 draw with Bury at Vale Park; his performance also saw him named in the Football League Paper's team of the week. Manager Michael Brown said, "I thought he mixed his game up well - short and long passes, broke it up, forward runs, wanting to do well". He was again named as Vale's man of the match after a shortage of defenders saw him play at right-back in a 2–1 home defeat to Bradford City on 25 February. However, he picked up a hamstring injury in mid-March, and was ruled out for the rest of the season. Guy made his Derby debut on 12 September 2017, in a 3–2 defeat at Barnsley in the EFL Cup. On 12 January 2018, he returned to League One on loan at Bradford City on loan until the end of the 2017–18 season. "Bantams" boss Stuart McCall said that " give us a little bit extra depth. He is hungry enough, however, to want to push himself into the starting XI". It took until his tenth appearance for Bradford for him to be on the winning side, when he was named as man of the match during a 1–0 victory over Gillingham.
Blackpool
On 31 August 2018, Guy joined League One side Blackpool on a loan deal until the end of 2018, with the deal due to be made permanent in January 2019, at which point he would sign an 18-month contract with the option of a further 12 months on top of that. He scored on his Seasiders debut with a 25-yard volley in a 3–3 draw with Macclesfield Town in an EFL Trophy group stage game on 4 September. The permanent deal was confirmed on 2 January. He ended the 2018–19 season with 24 appearances to his name. On 27 November 2019, he was sent off after receiving two bookings in a 3–1 defeat to Scunthorpe United at Bloomfield Road.
Carlisle United
On 30 January 2020, Guy signed an 18-month deal with EFL League Two side Carlisle United after moving for an undisclosed fee. Carlisle head coach Chris Beech told the club website that Guy was a "marquee signing". However he picked up a knee injury in his third appearance for the "Blues" and was ruled out of action for the rest of the 2019–20 season after undergoing surgery.
