Dear Liz: I currently have a 401(k) and an IRA, but want something more. A longtime CPA, who is very close to our family, recommended that I buy some stocks, but I’m unsure how to go about this.

Answer: When you’re investing, it’s important to be diversified. That means you should spread your money among different types of investments so you don’t have all your eggs in one basket, so to speak.

You’d need hundreds of thousands of dollars to be properly diversified with individual stocks. When you’re just starting out, it’s a lot smarter to buy mutual funds or exchange-traded funds that invest in a wide variety of stocks. Vanguard Total Stock Market ETF, for example, invests in more than 3,600 companies and has an ultra-low expense ratio of just 0.05%.

The fees you pay for your investments are important, since high expenses can dramatically reduce your total returns. Funds that try to beat the market, rather than match it, often engage in a lot of trading that drives up costs. Funds sold through full-service brokerages can carry high expenses as well.

So look for a discount brokerage that allows you to invest with minimal fees and commissions. Or consider one of the new breed of online advisors, such as Betterment or Wealthfront, that offers a low-cost basket of investments that are selected, monitored and rebalanced using sophisticated technology.

Dear Liz: If I plan to stay invested for more than 15 years and I can tolerate the ups and downs of the market, why would I want to put any of my 401(k) money into bonds instead of putting it all in various stock funds? The bond funds in my 401(k) have a five-year return of 5% to 6% whereas the other funds are 8% to 13%.

Answer: If you look at the more recent performance of those bond funds, you’ll notice that their returns are considerably worse. Many have been losing money lately as interest rates have risen. That poor performance may worsen if the economy improves and rates continue to rise.

But you need to consider more than recent performance when allocating your portfolio. Bonds and cash can cushion your account against big downturns in the stock market. That can help keep you from panicking and selling at a bottom.

If you’re as risk tolerant as you think and decades away from retirement, you might be able to put as little as 10% of your portfolio into bonds and cash. If you’re 15 to 20 years from retirement, a 20% bond allocation may be more prudent. A fee-only financial planner can help advise you about sensible asset allocations, or you can check out the stock and bond mixes of target date funds offered by leading mutual fund companies (such as the Vanguard Target Retirement 2030 Fund, if you’ll be retiring around 2030).