Drawing endless doodles while your attention should be elsewhere is a compulsion usually associated with distracted school students. Yet, all the while Mark Denton was climbing the ranks of adland, he couldn’t stop doodling away in meetings.

With a dozen filing cabinets overflowing with his experiments on paper, some of Denton’s works are being pulled out of the archive and into the Jealous Gallery space in east London.

Some are hidden gems that have never seen the light of day, others were the genesis of ideas that went on to be “snapped up by clients”. The work comprises original paintings by Denton featuring a screenprint overlay, and combines a cartoon aesthetic with often colourful language.

The name of the show might sound self-deprecating, but it’s actually meant to be a celebration of Denton’s creative impulses. As the gallery puts it: “It’s not shit. It’s Mark’s shit. It happens daily, there’s no holding it back.”

Everyday drawings might sound like throwaway remnants of the creative practice, and the selection process of the show may seem rather haphazard – “I just grabbed a pile and painted as many as I could in the lead up to the exhibition,” Denton explains. But as he points out, “no idea makes it into the filing cabinets if I’m not happy with it”.

Denton believes these everyday sketches have had a part to play in his lengthy career. He recalls lectures about advertising being “a young person’s game” back in the 1970s, but has enjoyed nearly five decades in the industry, doing everything from running his own agency to recently acting as an intern at St Luke’s in London. “Given that I started a career in advertising nearly 47 years ago,” he says, “I think that having ideas on tap has helped me last this long.”

The Shit Show by Mark Denton runs from Feb 2-26 at Jealous East, London; jealousgallery.com