Jacob Schwartz is a hair colorist and the hair color trend ambassador for Schwarzkopf. He's worked with a ton of big names, including Bella Hadid, Troye Sivan, and Sydney Sweeney.

how to ask your stylist for the same color, and how to keep Brat black looking fresh and shiny. Here's the thing: Charli's always had a signature look—saturated, ebony hair color complete with ...