Throwing three coins:

A traditional legend holds that if visitors throw a coin into the fountain, they are ensured a return to Rome.
Other vertion says that three coins should be thrown into the Fountain to folow the tradition, bun no much people know that those three coins were thrown by three different individuals
An actual interpretation of that tradition is that two coins will ensure a marriage will happen soon, while the third coin leads to a divorce.
The lucky way to throw the three coins is: with your right hand over your left shoulder into the fountain.
Near 3,500 Euros are thrown and collected from the fountain every day.