Foghorns. Buoys. Lighthouses. They all warn sailors about hazards that could strand, or even sink, a vessel.

So wouldn’t it be great if there were a foghorn for your portfolio to warn you of a possible investing misstep? Unfortunately, the only way to escape a dunking is to avoid common mistakes that could send your investments plunging into the deep.

How Far to the Shoreline? You need to define what you’re investing for if you want to move closer to your goals. Consider income-generating investments such as bonds or Treasury bills if your goals are short term. Long-term goals — like retirement — may benefit from significant exposure to equity investments, which have the potential to earn higher returns over time.

Too Many Fish. Make sure you own a variety of investments from the three major asset classes — stocks, bonds, and cash. Holding too many funds with similar objectives and investing styles could undermine your returns and create more risk in your portfolio.

Map Out a Course. Set up specific “sell” criteria, such as a percentage loss or gain or a period of time that an investment’s performance has to fall below an appropriate benchmark before you move on. And give a new fund manager a reasonable time limit to demonstrate performance before you take action.

Don’t Rock the Boat. Try not to overreact if the markets take a dive. Waiting out a slump is often your best option.

You should consider the fund’s investment objectives, charges, expenses, and risks carefully before you invest. The fund’s prospectus, which can be obtained from your financial representative, contains this and other information about the fund. Read the prospectus carefully before you invest or send money. Shares, when redeemed, may be worth more or less than their original cost.