You can plan for a secure retirement only if you have an idea of what you’re shooting for. In future chapters, we help you refine your retirement savings goals and set the size of your target nest egg, but here are some good rules of thumb.

Save at least 10 to 15 percent of your income toward retirement. Saving this amount will help build your nest egg and keep you living a lifestyle that accommodates your habitual savings. The savings cushion you create in your budget will give you some flexibility if temporary expenses—like child care costs, job loss, or major medical costs—force you to stop saving for a while. It will also ensure that the lifestyle you get used to while you’re working isn’t so expensive that you have difficulty saving enough to cover it later.

Your retirement income should come from a diversified selection of sources: Social Security or pension payments, retirement plan withdrawals, and investment earnings. As a rough estimate, save and invest enough so you won’t need to withdraw more than 3 or 4 percent per year from your retirement plans and investments to supplement Social Security or pension to meet your retirement income needs. Following that rule of thumb, if your retirement nest egg totals $500,000 and you’re retiring today, plan on withdrawing no more than $20,000 of your nest egg each year.

Over the course of your work life, any number of circumstances could interrupt—or at least reduce—your ability to save for retirement. The key is to not let these interruptions derail you permanently. If you’re diligent about regularly saving, short-term setbacks won’t derail you as long as you keep your eye on your goal of protecting your nest egg and achieving your retirement goal.