We live paycheck to paycheck. Is there a certain amount of money we should have saved in case of an emergency?

You’re sitting there silently hunched over a mound of bills and other expenses you and your spouse have accrued over the last month and you think, if only Mr. Gates would send me one of his weekly paychecks—’ol Billy-boy could do without it, right? But that’s not going to happen. So instead of wishing, it’s time to start doing.

The rule of thumb is that you should have an amount to cover from three to six months cash outflow (the amount you spend), available at all times. The next obvious question is: how does one set aside money for an emergency fund? It’s all about the cash flow!

The most effective way a couple can manage cash flow and ensure they have an emergency fund to fall back on is if they have a spending plan—"plan" being the operative word here.

Planning how you will spend your income is the most basic aspect of money management. Once you have calculated your cash inflow, the amount a couple receives from their paycheck(s) after deductions for taxes and employee-paid benefits, you can begin to deduct your cash outflow, which consists of the most necessary items like rent or mortgage, utilities, groceries and commutation expenses.

Planning is what makes the difference between ending up in debt and ending up with an emergency fund and a nest egg. But for a financial plan to succeed, you must set very specific, reasonably attainable goals that are measurable and then prioritize them. Calculate how much money it will take to achieve those goals and establish a timeline for when the money must be available to meet them. For example, couples tell me they want to buy a home before they start their family. That goal is too vague. You need to determine how much the home will cost, how much you will need for a down payment, and how much the monthly mortgage plus taxes and expenses will be. Then the goal is measurable—it has a dollar value.

Most couples wonder how they will "find the money" to save for their goals. It isn’t easy, but it’s doable. To get started, write down just about every penny you spend for at least one month. Somewhere in that list of expenditures are things you can do without, and this is where you can begin to set aside money for emergencies. That means you may need to cut back on the $4 lattes and weekend golf trips, even if you have a caffeine fix that seems like an emergency.

Dodie Theune is the Senior Vice President for the Bryn Mawr Trust Company.