Imagine traveling the world without spending a dime on expensive flights and hotels. While it may seem like a dream, savvy travel hackers Chad and Hannah Janis accrued 2 million credit cards points, quit their jobs, and have set off on an eight-month adventure to 40 countries — for free.

The Janises have been travel hacking for several years, and started after Chad scored a free flight for a job interview. Since then, they’ve used their points to fly to South Africa for just $72, Iceland for free, and spots around the U.S. for just $11.

Once they moved to New York, Chad wanted to take their travel hacking to the next level.

“We’ve been doing travel hacking for a while, and when we came out to New York, we had this idea of, let’s try and get as many points as we can and then book an around-the-world ticket and see how far it takes us,” he says.

While it sounds spur of the moment, Hannah says she needed to warm up to the idea in the beginning.

“At first I was like, I don’t know if that’s going to work out, but then, I thought, we can take more time because we have the opportunity,” Hannah says. “We have more time than money, so in the end, I was ready for it.”

Over the past year, they’ve opened up 26 credit cards, keeping track of minimum spends on a master spreadsheet. Once they spend enough to get the sign up bonus, they score tens of thousands of points they can redeem for flights and hotels around the world.

They’ve turned this hobby and that master spreadsheet into a website, Wall Street Minimalist, which offers travel hacking advice, and helps their users find the best credit cards to maximize points for free flights and hotel deals.

Want to travel like Chad and Hannah? Here are their travel hacks:

• Pay attention to credit card bonuses

The Janises’ biggest travel hack is paying attention to sign-up bonuses. As long as they spend a certain amount of money in a certain amount of time, they’re rewarded with thousands of points.

“We had to think about how much money we were going to spend on normal everyday living and how could that transfer to everyday credit card usage,” Chad says.

Their favorite credit card for beginners is the Citi Thankyou Preferred Card, which can help build your credit score and earn rewards before you expand into higher earning options.

• Plan your destination first

The Janises recommend deciding on your destination first, instead of letting the points dictate where you want to go. Doing the research on routes and rates will help you find a credit card that can pay for your trip.

“We’ll go get the card that earns towards that airline and book for free,” Chad explains.