Do was born in Biên Hòa, Vietnam, and moved to Philadelphia at fourteen. He attended the Fashion Institute of Technology in New York, graduated in 2014 winning the LVMH Graduate Prize, then worked at Celine and Derek Lam before striking out alone. His designs have been worn by Zendaya and Beyoncé.
From 2023 to 2024 he served as creative director of Helmut Lang, debuting a Spring/Summer 2024 collection rooted in accessible, high-quality wardrobe staples; The New York Times called it 'accomplished, accessible, and very commercial.' He left in November 2024 and launched a more affordable offshoot, PD-168, in 2025.