At the margin, that is.
Information in the modern world is virtually free, and well-defined tasks can be outsourced very cheaply, if need be. Don’t specialize in those.
Bias is everywhere, and overcoming bias yields great gains. Empirically, our biases stem strongly from our nationality, our language, and our cultural background. (It is, by the way, remarkable how much libertarianism is an Anglo-American phenomenon.)
To overcome those biases we should travel, spend some time living in other countries, and learn other languages. In other words, the more knowledge is held in the minds of other people, the more competent we wish to be in assessing who is right and who is wrong, and that requires exposure to lots of different points of view.
Judgment, judgment, judgment. That’s the scarce asset which most people underinvest in, and which yields especially high returns. It can’t be outsourced very well either.
Marketing is becoming all-important as well. That also requires judgment and the ability to see things from other people’s points of view. Again, live abroad and learn other languages.
At the very least, date foreign women (or men).
It is in contrast a common presumption that learning other languages, for English speakers, is becoming obsolete, if only because so many other people speak English. I would think this raises rather than lowers the return to learning other languages. Last fall, while visiting at Middlebury economics, I voiced these opinions and encountered little agreement.
Addendum: Here is commentary from Ed Lopez.