It may be the biggest worry of retirement: How do you ensure that you don't run out of cash before you run out of breath? The easy answer is to save early and often and build up an impregnable stockpile of cash. If you've missed that memo, however, you can still vastly increase the chance that your nest egg will last at least as long as you do by taking these six steps.

1. Make a Plan

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Just 48% of Americans have attempted to figure out how much money they should be saving for retirement, according to a 2015 survey by the Employee Benefit Research Institute. Notably, the study found that those who have tried to calculate their retirement needs have more savings and greater confidence in their retirement readiness than those who have neglected to make a plan.

To set your saving target, start by estimating how much income you'll need to replace in retirement (one rule of thumb is 80% of your working income). Factor in how much you spend