If I'm judging you, I'm wrong. If I'm condemning you, I'm wrong. If I'm criticising you, I'm wrong. Even when I'm right, I'm wrong: even when the fragments of reality I perceive are actually there and are correctly perceived, the picture I construe is wrong.
Here's the corrective measure: always view the other in an optimally charitable light: everyone in innocent; there is blindness, and flawed thoughts and behaviour flows therefrom; but guilt is unreal. When I hold you guilty, I set myself apart: any unkind thought I allow diverts me into a dark nothingness, separate and crowned.
I do not think it is possible me to perfect my generosity of spirit. In a sense it is the only virtue, and its perfection the only task, as it is the calibre—in both senses—of the channel God uses to reach others through me.