Here's the formula:
Get accepted as an instructor at Vail, Beaver Creek, Deer Valley, or Sun Valley.
Spend the next ten seasons doing ONLY private lessons for Middle Eastern oil sheiks, Russian mobsters, Hong Kong entrepreneurs, European ex-royalty, and American hedge fund runners. Make sure you do Google research on every prospective client that the ski school tries to assign to you and don't accept anyone whose estimated net worth is less than 500 million (dollars, pounds, euros).
Treat them like kings and make certain every tiny portion of their ski vacation is perfect.
By the end of the ten years, your tips should outdo your ski school wages by about 50 to 1 and you should be set up for life.
Alternatively, you could just accept the fact that you might make just enough money to have a wonderful lifestyle in a fabulous location and meet great people along the way. That's the more likely scenario.