As anyone who has been near Instagram or Facebook this week will know, Britain is in the grip of a no-makeup selfie epidemic. To wit: users are posting barefaced pictures with the hashtag #nomakeupselfies, raising more than £8m for Cancer Research in the process. Before #nomakeupselfies found a purpose, however, the trend started, like so many things, on celebrities’ Instagram accounts. Here, Beyoncé, Lorde and Lupita show us how it’s done