Last year, legendary makeup artist Pat McGrath DBE created a porcelain-doll glass finish on the models for John Galliano’s Maison Margiela Artisanal show — and I was completely captivated.

It’s hard for a designer to get the world’s attention at fashion week. But a year ago, the Maison Margiela show went viral thanks, in large part, to Pat McGrath’s makeup, which made models ...