A step you can take to raise self-esteem of others is by expressing appreciation. One of the deepest cravings of human nature is the need to be appreciated. Whenever you express gratitude or appreciation toward another person for anything that the other person has done, you make him or her feel more valuable, more competent and more worthwhile.
All it takes to express appreciation are the simple words, “thank you.” The words “thank you” are two of the most powerful in the English Language, and the most powerful single expression in virtually any language. I have traveled and worked in more than eighty countries, and I have learned that you can get halfway across any country in the world by simply learning and saying the words “please” and “thank you” everywhere you go.
— extract from Brian Tracy’s Maximum Achievement.