What do you want to do sadhana for? The aim should not be the satisfaction of egoism: "I want to be a great yogi; I shall have so much power and with that power I shall establish myself in the world." All such thoughts must be thrown far away.
Of all evil I deem you capable: Therefore I want good from you. Verily, I have often laughed at the weaklings who thought themselves good because they had no claws.
Nobody really likes to be lectured a lot. And, therefore, if you want to be an effective person, what you don't do is scold the person publicly all the time.
Love and do what you want. If you stop talking, you will stop talking with love; if you shout, you will shout with love; if you correct, you will correct with love.