Okay...stop guessing. It's a trick question because there's actually no lipstick involved. I stole a tip from Kim Kardashian's makeup artist, Mario Dedivanovic:
I applied a tiny* bit of foundation (here, Clinique Superfit Makeup in Nutty) to partially cancel out the pink tones in my lips; then I coated my lips in MAC Clear Lipglass.
Genius!
*Make sure you just use a tiny bit of foundation. Too much will have you looking like crackhead Tyrone Biggums from Chappelle Show.