Usain Bolt says - " If you make $10 , save $6". And then you can figure out what to do with the rest of the money , whether to spend it for something important or use it for luxury. He suggests it's better to spend those left over money after saving on paying bills and other important stuffs. So the concept is simple to get rich or to become financially independent, one should always try to maintain higher percentage on saving money than spending it.