Being non-judgmental , for me, is less about actions and more about the concept of free-will. I will definitely judge a person’s actions as right (as per my own subjective standards). If somebody does something nasty, I am going to say that the person has done something awful. But I cannot say that the person is in complete control of what he/she did. There are a million factors that influence a decision. I cannot get inside that person’s mind to know the truth.
Coming to everyday life where you make judgements like “This person is lazy” or “This person is selfish,” maybe you don’t have to be non-judgmental about someone’s selfishness or laziness. But what you can accept is that you don’t have full knowledge about that person. And you feel peaceful because when you assume that people are in control, you obsess about what they could have done. And then, you start hating them..which only destroys your peace. But if you admit that they are selfish or mean but also open your mind to the possibility that you don’t know about all the factors that contributed to the choice, you will hate them less.