You cannot change another human being. Think how hard it is to change yourself! And even if you could, you would only bring them away from their purpose – changing themselves.
We can, however, provide help on physical, mental, emotional, or spiritual levels. We can attempt to influence others in ways we think would benefit them. We can try to act in a manner and make decisions that would serve as a positive role model.
But we must navigate the razor’s edge between teaching and preaching. Teachings means sharing your wisdom out of love and care, not because you want to convert or convince or coerce.