Developed in-house, with media bought by the7stars, posters will run in London and Manchester and carry the slogan: "Join The Fashion Line Up".
They will be supported by display, online and social platforms, to find a new model. Entrants must be "dressed to party" and the concept aims to push party dresses in the run-up to the festive season.
Nitin Passi, chief executive of missguided.co.uk, said: "We wanted our first multimedia campaign to engage consumers by offering the possibility of bringing their fashion dreams to life. Moreover, we wanted to invite consumers to share dialogue with us and each other, encouraging them to develop a deeper relationship with the Missguided brand"
Modelling hopefuls can send in pictures of themselves to email@example.com, the Missguided.co.uk page, or to via social media.
Missguided.co.uk launched in April 2009 and has expanded to more than 100,000 unique users. It has diversified into cosmetics with its own Missguided nail polish.