2. Mind the Undertones
Not all greys are created equal. Some have blue undertones, some have green, and others are warm (leaning toward brown). Before you commit to a paint color, test it in your room at different times of the day. A grey that looks perfect in the morning sun might look like a cold concrete bunker by evening. Similarly, ensure your yellow isn’t too “highlighter” neon unless that is specifically the industrial look you are going for; aim for mustard, butter, or saffron for a more sophisticated feel.