The three-account system that stops you thinking about money
You check your account balance before buying something that isn’t essential. The number looks big enough, so you buy it. Ten days later the building maintenance fee hits and throws off your whole month, because that “big enough” number was already spoken for without you knowing it. It’s not that you’re spending badly: it’s that a single number doesn’t tell you which part is actually yours to spend.
The tip: let your money live split up, not together
The idea is simple and doesn’t depend on doing any mental accounting: split your money into three physical accounts, each with one job.