Advocating a flexible approach to stock-picking, a recent article by Barron’s veteran Andrew Bary offers some guidance that incorporate the ever-successful strategies of Warren Buffett while emphasizing the importance of creating a “well-diversified portfolio before trying to pick individual stocks.”

He writes that Barron’s tends to favor both value stocks (those with low price-to-earnings or price-to-book ratios) and growth companies (those with rapid earnings and revenue growth) and outlines the following guidelines:

Paying for growth—when buying growth companies, “look for dominant businesses and don’t overpay”—he suggests no more than 25 or 30 times projected earnings for the next year. “Be careful about fads,” he warns.

Assessing value: Bary advises investors to find companies with some earnings growth or choose those that are “valued so cheaply relative to book value or earnings that they don’t need much growth to be good investments.” He describes a low valuation as less than 75% of book value or eight times earnings. He warns against getting discouraged by an high absolute stock price which, “in and of itself, has nothing to do with valuation.”

Sector pros and cons: Pharma stocks, he writes, can be “tough to assess because their prospects often hinge on the success of new drugs, which can be hard for most investors to analyze.” Dividend plays such as utilities and telecom stocks, he says, “can be rewarding even without much stock-price appreciation” and consumer stocks, which have come back since the Trump victory, may not be cheap but Bary says to “think of them like bonds with increasing dividends.”

His final rule for picking stocks is to be patient. “It can take some time for the market to come around to your thesis,” he writes. “Trading in and out of shares is rarely a formula for success.”