Big ideas--we all want 'em. We've all thought, at one time or another, "I could have come up with that!" Big ideas are like gold, especially when you are prepared to put in the work and the effort to make them come alive.

So as we get close to kicking off a new year, you may be thinking, "How can I come up with that next big idea?" Jonathan Swanson, the co-founder and president of Thumbtack, created a rigorous process to come up with the idea for his business--a platform that connects customers with trusted service providers in a range of industries--which he says has the potential to "reshape a huge slice of the U.S. economy."

But it took a while to get there. How, exactly? I recently sat down with Swanson to uncover his method for generating world-changing ideas.

How did you come up with the idea for Thumbtack?

We did what you're not supposed to do--we started a company before we had an idea. My partners and I had this desire to make a big difference in the world. We knew the best way was to solve a really big problem that doesn't just affect us, but affects large numbers of people all over the world.

We went out looking for big problems that affected hundreds of millions of people in all walks of life. My partners and I would have a phone call every week where we discussed and brainstormed different ideas. The heuristic was, "Let's look for a problem that affects hundreds of millions of people and that we think can be solved with the application of technology." That was our search criteria--when we searched Google, we were searching the world for startup ideas and our search was "big problem and can be solved with technology."

We would talk and brainstorm different parts of life that were broken or frustrating. Whenever we had an idea that was interesting, we would dig into it more and break it up and we would split up homework and research. We would see if it was promising or if others were working on it and come back in a week and repeat the process. What we found was that there were problems that were superficially interesting and lots of problems that were big problems, but once you dug into them, they were harder to fix than we imagined or lots of ideas were already being worked on by lots of people. Basically, we repeated the process for over a year.

What are the signs that an idea is a good one?

The most important thing is that it solves a problem that affects lots of people. That is the heuristic for knowing that you're solving a problem that is worthwhile. The second thing that is harder is knowing that you have the technology or solution to solve that problem. It depends on what sort of company you are starting. Sometimes that means that you want to get into an area where people haven't started and you are first to market. When we came up with the idea of launching a financial-management aggregator, we discovered Mint. We felt that Mint was so far ahead of us that it didn't make sense for us to try it. However, with Thumbtack, the more we dug into it, all the current solutions were old. Nobody had re-imagined how customers and professional services could come together in a service marketplace. For us, we found that we are solving a big problem but we also had a new view of how it could be solved. We had an idea that had not come to life.

What excites you about Thumbtack?

The most exciting thing is that we get to reshape a huge slice of the economy. Ebay, Amazon, and Zappos have changed how you buy products, but nobody has redesigned the service industry. The Yellow Pages are 100 years old. Yelp and Angie's List are iterations of the Yellow Pages. Half of the economy has not been disrupted in the last 100 years and we have the opportunity to change how people buy and sell services. The scope is really exciting and we get to change the quality of service in a meaningful way. With Uber, the quality of service is really high--they offer you a mint and water. In a taxi, the service is not great. It's not that Uber has hired different drivers; the difference is that Uber has data on the quality of the drive and uses that data to incentivize the driver to improve the service. It's really fun to be a part of such a big project.

What advice would you give to aspiring entrepreneurs who want to come up with their own big ideas?

First, solve a problem that affects a lot of people, not just yourself.

Second, you really need co-founders to explore ideas. It's really difficult to do that on your own. Having people you trust and respect that you can bounce ideas off of tremendously benefits the ideation and brainstorm phase. It's also a lot more fun.

Finally, you need to have a kind of contradiction of confidence and humility. You have to have the confidence to do something that has never been done, but you also need to have a lot of humility, because nothing is more humbling than entrepreneurship. You learn a lot about yourself and make a lot of mistakes. You have to very quickly own up to your mistakes. Having both confidence and humility simultaneously is important, but difficult.

How can you tell if an idea has the power to change the world?

The easy answer is that if you are solving a problem for hundreds of millions people, that changes the world. If it's something that is frustrating for that many people and you solve it, you're helping the world in a meaningful way. The challenge with entrepreneurship is that you don't know if it's going to work, and if it's obvious that it's going to work, it wouldn't be a good startup because lots of other people would have done it. Along the lines of having confidence and humility, you need to believe that the idea can change the world, and you have to have the grit to stick it out--often for years--while you are making it happen. You have to be willing to go through the ups and downs of the roller-coaster entrepreneur life.