Retirement planning can seem like a daunting task—especially for self-employed individuals without access to company-funded 401(k)s. And as an entrepreneur, creating a plan to step away from your business is likely not your number-one priority.

But when it comes to retirement planning, time truly is money—the longer you withhold your investments, the more you're missing out on the opportunity to grow your nest egg.

Fortunately, you don't need a conventional 401(k) to set aside retirement money. With these five tips, you can help save—and potentially supercharge—your hard-earned income.

1. Open a tax-advantaged account.

The first step in safeguarding your stress-free retirement is to open a tax-advantaged account ASAP. These four alternatives to 401(k)s are great options for entrepreneurs.

SEP-IRA

The SEP-IRA is a good option for a self-employed individual because you can contribute up to 25 percent of your annual earnings. You can also choose to contribute a smaller percentage of your compensation during slower years.

In a SEP-IRA, the employee's annual contribution must match the employer's. So, if you'd like to contribute the maximum 25 percent of your salary after a lucrative year, you must do the same for all of your employees—a limiting factor for small enterprises with employees, but an opportunity to boost savings for a single self-employed business.

One-Participant 401(k)

The Solo 401(k) is essentially the same as a conventional 401(k). The difference? It's in the name: Only self-employed individuals with no employees, plus their spouses, are eligible for this plan.

Under this plan, the account holder can elect to defer up to 100 percent of their earned income. In addition, the account holder can top up their account by contributing up to another 25 percent of their compensation per year.

Be advised: the account holder is required to file an annual report if their business acquires $250,000 or more in assets.

Traditional IRA or Roth IRA

Traditional and Roth IRAs are similar. Annual investment amounts, for instance, are the same for both.

Here's the major difference: Contributions to the Traditional IRA are made in pre-tax dollars and are tax deductible. Contributions to the Roth IRA, on the other hand, are made after tax, but withdrawals in retirement are tax-free.

Further, contributions to a Roth IRA are made according to your current tax bracket—not the tax bracket you'll be in when you retire. That makes the Roth IRA a good option for self-employed folks at the beginning of their careers. If you expect to be at a lower tax bracket by the time you retire, a Traditional IRA might be a better choice for you.

So, you've opened your tax-advantaged savings account. Congratulations! Now it's important to know when—and how much—to invest to keep that nest egg growing.

2. Diversify your portfolio.

Spreading your investments among a range of assets can mean a greater chance of reward in the long run, plus a potential safeguard against market volatility. You may want to try investing in a mix of stocks, bonds and cash.

If you're further from retirement age—and able to stomach a drop in your portfolio value—you might consider investing more in stocks than in bonds. If you're closer to retirement age, you might consider leaning more heavily toward stable bonds and lower-risk stock investments. Generally, cash investments offer the lowest return compared to other investments.

To minimize volatility and increase potential earnings, also consider diversification within those three asset classes.

3. Consider opening a target-date fund.

Target-date funds are mutual funds that automatically rebalance stock and bond investments over time. The titular “target date" refers to the year that the account holder plans to retire, and the fund manager decides how to rebalance the account holder's assets accordingly.

These funds are an attractive option for those who don't want to worry about actively monitoring their investments. However, the formulaic mix of stocks and bonds also means these funds may lack the flexibility to shift assets into promising trends or pull out of weaker ones.

4. Revisit your portfolio.

No matter how you choose to design it, think of your asset portfolio as a living document; due to changes in the market, your portfolio's total value fluctuates over time. Make adjustments according to big trends or shifts in the market, a turnover in the calendar year and major life events such as buying property or having children.

However, most advisers will agree the best strategy is to save what you can and, once you've made your investment choices, leave the money alone and let it work for you.

5. Save, save, save.

According to a 2017 survey of 1,960 small-business owners by Manta, 34 percent of small-business owners don't have a retirement savings plan. Of that 34 percent, 37 percent say that they don't make enough profit to save for retirement.

While there's a cap on contributions to all of these accounts, there's no minimum required. Setting aside a few thousand dollars this year will make a difference in the long run. You might have to cut corners elsewhere, but the peace of mind you'll gain will be worth those small sacrifices.

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