1. When you greet somebody, shaking his hand, accompany the greeting with a smile, which must not compete Mona Lisa's. It must be just natural, spontaneous, outspoken, devoid of artificiality.
2. Do not stretch the hand first to a woman, an elder person, a superior or a boss. The man should not be the first to stretch the hand, nor the younger or the subaltern. In these situations, it is enough to bend slightly the head and wait for the person to stretch the hand.
European researchers have created a robotic hand that mimics the flexibility and sensitivity of a human hand, and is controlled by a neural-network-based program modelled on the cerebelloum.