No matter what type of eyeshadow look he's creating, Mayo has one product that he relies on every time to really make the look pop. "I get asked all the time, 'How do you get eyeshadows to be so vibrant or to be so saturated?' and I would not be able to do that without an eyeshadow primer," said Mayo. "And specifically, the Urban Decay Eyeshadow Primer Potion (£19.50) is my secret weapon."