6 Smart Investing Tips From A Totally Trustworthy Financial Adviser: Mom

A 2015 survey by Creditcards.com reported that Millennials consider mom their biggest financial influence. But that same survey also suggests that mom's sway wanes as we age. Which is a shame. Because mothers (even those with little or no financial background) typically dole out smart advice that you can apply to your investing, even if it's not couched in financial terms. So in honor of Mother's Day, here are six nuggets of maternal wisdom you've probably heard at one point or another in your life, along with my explanation of how each can translate into financial success.

1. People in hell want ice water. I heard this phrase whenever I asked for something that I desperately wanted (say, money for a bike as a kid or, in my teen years, a car) but my mother felt was beyond our means. Translation: Just because you feel you need something doesn't mean you can have it. So when you're tempted to stretch for yield because you're dissatisfied with the paltry 1% or so available at the highest-yielding FDIC-insured money-market accounts accounts or you're thinking of loading up on tech stocks or emerging market funds in an effort to juice your portfolio's performance, remember that just because you feel you need higher returns, doesn't mean they're achievable (at least not without taking a lot more risk).

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2. You won't be happy until you break that, will you? Mom usually unloaded this classic just as you were on the verge of destroying a new toy you were given less than an hour before. The investment corollary here: We go to the trouble of building a perfectly decent diversified portfolio, and then proceed to muck it up by investing in every gimmicky new mutual fund or ETF that comes along. The simple truth is that the more you expand beyond a basic blend of stock and bond funds (preferably low-cost index funds), the more likely you'll end up "di-worse-ifying" rather than diversifying. A truly smart investor is one who knows when to leave well enough alone.

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3. God gave you a brain. Use it! Intellectually, we know that there's no free lunch in the financial markets. A higher return always comes with greater volatility, not to mention other potential downsides. Yet, somehow many of us still get sucked in when an adviser (or salesperson posing as one) comes along with a pitch for a magical investment that's supposed to provide lofty guaranteed returns or give you the upside of the stock market while protecting you against the downside. The best way to avoid falling for the investment flim-flam du jour: Follow mom's advice and put that brain to work.

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4. Eat your vegetables, they're good for you. What's the investing equivalent of eating your spinach and broccoli? It's doing those mundane-but-critical chores like making sure your portfolio is truly diversified among different types of stocks and bonds and not a mish-mash of overlapping holdings; assessing your risk tolerance to ensure you're not investing too aggressively or conservatively; and rebalancing that portfolio periodically to maintain the proper balance of risk and reward. Granted, such activities might not be as exciting as putting money into a hot new ETF or speculating on the price of gold. But just as mom knew that getting your veggies was essential to your physical well-being, so too is being disciplined about performing these basic tasks central to maintaining your portfolio's health.

5. If everyone else jumped off a cliff, would you do it too? Okay, I'm sure you have enough common sense that you wouldn't jump off a cliff (or a bridge, the option preferred by some moms). But history shows that investors are all too willing to abandon common sense and plow billions of dollars into overpriced IPOs, tech start-ups with more buzz than profits and just about any other fad the Wall Street marketing machine churns out. So the next time you're considering buying into whatever market sector is sizzling or moving a big chunk of your portfolio into stocks because the bulls are stampeding, think back to mom's question—and resist the urge to join the lemmings as they fling themselves off a financial cliff.

6. Don't break your arm patting yourself on the back. I saved this one for last because I think it gets to one of our biggest weaknesses as investors, one that makes us vulnerable to many other problems. I'm talking, of course, about overconfidence.

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University of California-Berkeley finance professor Terrance Odean has practically made a career of chronicling how overconfident investors sabotage themselves by trading too frequently. But there are plenty of other ways overconfidence does us in, ranging from buying hot stocks and funds because we're sure they'll repeat their recent success (which they often don't) to crediting ourselves for the stellar returns we earn during bull markets when in reality virtually all stocks were rising and we were really just along for the ride. This overweening faith in our investing prowess is bad enough when the market is climbing. But mistakes like buying investments we don't know as much about as we think or loading up on stocks way beyond our tolerance for risk can really come back to haunt us when the market tumbles and stock prices plummet.

So enjoy your investment success. And by all means give yourself credit for being astute enough to build a diversified portfolio and for saving and investing for the long term. But remember mom's admonition: Don't get too cocky. Suffering investment setbacks is never pleasant, but it's even more of a drag if you're doing so while your arm's in a sling.

Walter Updegrave is the editor of RealDealRetirement.com. If you have a question on retirement or investing that you would like Walter to answer online, send it to him at walter@realdealretirement.com. You can tweet Walter at @RealDealRetire.