Don't depend all your life from one source of income, create multiple sources of income. There is no job security anymore, you can lose your job anytime, so get something else doing.
As a banker, you can also have a barber's shop and get people working for you. You can be a doctor and still have taxis working for you and every month, apart from your normal salary, you keep getting more money from other sources. That's making money work for you.
Even as a student, you can be studying and have a part time job or even self-employed. You can bake cake, design websites, take photographs, write articles and get paid, do anything you love doing and don't fully depend on your parents for money. Have multiple sources of income.