Long Term Vision: Where doth it come from?

How do you decide on what you want to accomplish with our life, and do it fast. I’m convinced that knowing what you want to do gives you 35 IQ points, no joke. People that just know what they want know what’s going on.

And this is talking long-term. I used to dream about what it would be like to be Muhammad Yunus, launching microloans into the modern era, and scaling in a way that allowed millions of people to gain access to financial means for the first time. Then he dedicates his life to keeping Grameen bank going, branching out into Grameen Phone, and all o f the associated goodness of Grameen. This man knew what he wanted- not just to help people, but he knew what he wanted to set up, run, and scale and it changed the world.

And so this is the very short question.

How can you know what you want to do longterm? Please provide a detailed step by step process if you can.