The Labour Party will crowdsource its next advertising campaign after inviting the public to design its new posters.

Labour is encouraging visitors to its website to submit their own poster designs which it will release on digital adboards over the Easter weekend.

The crowdsourced campaign has been inspired by the success of mydavidcameron.com, which was not set up by Labour but hosts a plethora of posters spoofing David Cameron's "airbrushed" campaigns.

"In recent weeks progressives across the web have produced some striking political imagery on websites like mydavidcameron.com," Labour's website says. "We’ve stood back and admired this work."

Labour has set two briefs. The first is to show its "pledge to protect frontline investment". The second challenge, more in tune with the mydavidcameron site, is to "Highlight David Cameron's lack of substance".

The - rather prompt - deadline for posters to be uploaded is 5pm tomorrow. Philip Gould, Labour's ad guru, has offered some pithy advice for those struggling to meet the brief: "Keep the message simple. Include strong images. Try to weave in humour wherever possible."