Social Security is only meant to serve as a portion of your retirement income. If you've been an average earner, it'll replace about 40% of the salary you took in during your working years.

Most seniors, however, need somewhere in the ballpark of 70% to 80% of their former earnings to live comfortably, so if you're not expecting to build a hefty nest egg, you'll need to eke as much money out of Social Security as possible. Here are four things you can do to increase your benefits.

1. Work at least 35 years

Your Social Security benefits are calculated based on your 35 highest-paid years of wages. But if you don't have 35 years of work on record, you'll have $0 factored in for each year you go without an income.

It therefore pays to aim to work for 35 years, even if it means extending your career when you're older and postponing retirement until your 70s. Doing so, however, might actually benefit you in two ways. First, you'll replace $0 years with an actual income, but also, that income might be substantially higher than it was when you first entered the workforce, thereby helping your benefits even more.

Smiling senior man wearing an apron and standing in front of a kitchen counter with olive oil, bread, and a salad on top of it.

IMAGE SOURCE: GETTY IMAGES.

2. Fight for raises during your career

The more money you make during your working years, the higher your Social Security benefits stand to be in retirement. Therefore, if you're able to boost your earnings, you'll wind up getting your hands on more money not just immediately, but during your golden years, as well.

How might you boost your income? Taking courses or obtaining professional licenses or certifications might result in a salary bump, so if you're willing to put in the time, it could pay off in a very big way. You should also stay on top of industry trends and continuously research salary data in your field to make sure you're being compensated fairly.

Sometimes, a little data showing you're underpaid is all it takes to give your salary a bump. Finally, do the best job you possibly can. Many employers reward high performers, and if you make the effort, it could translate into higher earnings.

3. Delay benefits past full retirement age

Though your Social Security benefits are calculated based on your top 35 working years, the age at which you file for them could cause that number to shift upward or downward. If you file at full retirement age, you'll get the exact benefit your earnings record allows for. That age is either 66, 67, or somewhere in between, depending on your year of birth.

You do have the option to claim benefits as early as age 62, but doing so will result in an automatic reduction that, in most cases, will shrink those benefits for life. On the other hand, if you delay benefits past full retirement age, you'll boost them by 8% a year up until you turn 70. That increase will then remain in effect for as long as you collect Social Security.

4. Retire in a state that doesn't tax Social Security

Most states don't impose a tax on Social Security, but there are 13 that do. If you retire in Colorado, Connecticut, Kansas, Minnesota, Missouri, Montana, Nebraska, New Mexico, North Dakota, Rhode Island, Utah, Vermont, or West Virginia, you could lose a portion of your Social Security income to state taxes, so retiring outside these states could help you get more money from your benefits.

Keep in mind, however, that if your earnings exceed a certain threshold, you'll pay federal taxes on your Social Security income. And that threshold isn't particularly high, which means that if you have an income source outside of Social Security, there's a good chance your benefits will be taxed to some degree, anyway.

Growing your Social Security benefits is particularly important if you don't expect to have another substantial source of income during retirement. Even after employing the above tactics, it still pays to do what you can to generate additional income streams. That could mean boosting your nest egg, selling a home and living off the proceeds of that sale, or getting a part-time job during retirement.

Your senior living costs won't necessarily be that much lower than your expenses during your working years, so the more income you're able to get your hands on, the better.