Instagram’s gua sha guru shows how to use a rock to fight wrinkles

Danna Omari has been posting skin care demos on Instagram for a few years now. But it wasn’t until she started showing off two then-obscure techniques — buccal (a specialty inner-cheek massage) and gua sha — that her popularity skyrocketed. And when it comes to gua sha (pronounced gwa sah), Omari’s timing couldn’t have been...