Warren Buffett always knew he'd be giving away a lot of money, and he always knew how he would do it: outsourcing.

In a video clip for a new online course on philanthropy that starts today, Buffett says he follows the lead of Adam Smith's division of labor. "I make it and somebody else gives it away."

One of the people he has entrusted with that task is his sister, Doris. Buffett says he's the "wholesaler" and Doris is the "retailer" when it comes to charity.

Her Sunshine Lady Foundation is associated with Learning By Giving, a foundation that "promotes the teaching of effective charitable giving" by supporting what it calls "academically rigorous full-credit courses with grants of $10,000 for each class to distribute to local nonprofit organizations."

Until now, those courses were limited to students attending participating colleges and universities. But on Monday they expand to the Internet with a massive open online course called "Giving With Purpose."

Taught by Northeastern University professor Rebecca Riccio, the four-week course consists of a series of videos with titles like "Why Do People Give," "What's Relevant to You?" and "The Challenge With Measuring Impact."

In addition, students can watch videos featuring guest speakers, including Warren and Doris Buffett, baseball Hall of Famer Cal Ripken Jr., and ice cream entrepreneurs Ben Cohen and Jerry Greenfield.

In his video with Doris, Buffett says that even before he became wealthy, he and his wife Susie agreed that almost all the money he made -- and he thought he would make a lot -- would go to society.

Initially, he postponed giving. "I thought I would compound a fund at a high rate, and therefore if I gave away all my money when I had a million dollars it would deprive the world of many billions later on."

Now, he says, "every share of Berkshire Hathaway I have will go back to society, and it doesn't cost me a thing. I get to do what I love doing every day, and I get to have everything I want."

(Buffett owns 336,000 Class A Berkshire shares with a market value of over $59 billion. That's after eight annual stock gifts to the Gates Foundation alone that would be worth $19.4 billion at its current price.)

What he loves doing, of course, is running Berkshire Hathaway. And he has no interest in managing a foundation. "I wouldn't be effective, as I wouldn't like doing it so much," he says.

That's why he's distributing his billions through foundations run by his friend Bill Gates, Doris, and his three children, HowardSusan and Peter.

Buffett's secret: "Figure out what you're good at and play that game. You don't have to be good at everything."

This story originally appeared on CNBC