Have Plenty of Liquidity

The rich make sure they have sufficient liquidity, or cash, to cover their short-term needs. They have an emergency fund, so "they don't have to disrupt their life for an unexpected occurrence," Kay said.

The fact that rich people have money set aside for rainy days isn't solely a function of their wealth. They have cash reserves because they are disciplined enough to save.

Everyone should aim to build an emergency fund with enough cash to cover six to nine months of expenses, Kay said. However, you don't have to set that much aside all at once. You just need to be working toward that goal with every paycheck. With that in mind, you should arrange to have a set amount automatically transferred from your checking account to savings each month.

"Like anything else, it's a goal," Kay said. "It only makes you a failure if you're not working on it."