Then he said "keep it real & say whatever's under your handkerchief"

from CyHi Da Prince – Hear Me Out Lyrics on Rap Genius

The customer gives him a bit of advice. A handkerchief is always on the left side of your suit when you are wearing one. Our heart is beneath our handkerchief so he’s telling CyHi to keep it honest and to always say what’s on his heart in other words his true feelings. The left side of our heart is larger than the right so technically our heart’s are not predominantly centered directly in the middle of our chests.

To help improve the meaning of these lyrics, visit "Hear Me Out" by CyHi Da Prince Lyrics and leave a comment on the lyrics box