The remaining contestants - Luisa Zissman, Dappy, Lee Ryan, Casey Batchlor, Linda Nolan, Ollie Locke, Sam Faiers and Jim Davidson - will be given 10 second warnings throughout the day before they have to pose for a picture.
A large camera has been set up in the lounge of the CBB house and Big Brother will make specific requests for the snaps.
One housemate must also hold a large black arm attached to the camera, to ensure their own arm is in the selfie.
In scenes yet to be aired, Big Brother told the housemates: "After three weeks of being confined in the Big Brother house, you are surely all missing your Twitter, Facebook Instagram and mobile phones.
"After being parted from social media for so long, Big Brother understands that some of you may be suffering severe withdrawal symptoms. Therefore, for today's task Big Brother is providing you with an outlet - a day of celebrity selfies."
Big Brother added: "When instructing housemates to pose for selfies, Big Brother may deliver specific instructions such as, Casey should take a selfie in a red dress."
To get things started, Big Brother asked the celebrities to pose for a group picture, which was then posted on the official CBB Twitter account.
Copyright: Channel 5