You know Sir John‘s name from his status as Beyoncé’s go-to makeup artist, but the beauty pro’s life wasn’t always so star-studded. Before he caught his big break assisting beauty legends like Pat McGrath and Charlotte Tilbury backstage at some of the biggest fashion shows, Sir John (yes, that’s his real name) worked at MAC counters in New York City by day and did makeup in strip clubs by night. In other words, he knows a thing or two about nailing great makeup, no matter your budget. From using glue stick as brow gel (really) to the best concealer-blending technique, here’s everything we learned from the L’Oréal Paris Makeup ambassador when we caught up with him in London.