Before his successful channel and becoming one of the richest youtubers, Olajide had a YouTube channel (which is still online) called JideJunior, which he created on April 24, 2008. Olajide opened his current YouTube account on July 24, 2009, with a video about the FIFA video game franchise. According to his website, YouTubers such as Weepeler and Hjerpseth inspired him to start his own YouTube career.
His main channel is primarily focused on FIFA, although he plays other games such as Grand Theft Auto V and other PC-based modifications on his secondary channel. Olajide family often appear in his videos, especially his younger brother Deji and his father.
His secondary channel (KSIOlajidebtHD) contains videos of him playing more casual, arcade and horror games in a manner similar to that of comedic horseman PewDiePie. Olajide also sometimes plays with his brother Deji Olatunji, who also owns a YouTube channel called ComedyShortsGamer.