PeopleThe Best Celeb Face Mask SelfiesColleen KratofilJuly 24, 2017 at 1:00 a.m.Link CopiedRead full article1 / 39KATY PERRYThe singer gave a thumbs up in a mirror selfie on her Instagram stories as she donned a sheet mask while wearing sunglasses and a baseball cap. Source: Katy Perry/InstagramThe Best Celeb Sheet Mask Selfies