In 2014, Steve Adcock, 36, and his wife Courtney, 32, decided to double down on their savings in order to retire early.
About two years later, Steve left his career in information technology at age 35. Courtney left her IT job in April 2017, and since, the two have been traveling the country full-time in a 30-foot Airstream trailer.
While the couple made good money — a combined $200,000 to $230,000 a year — their success boiled down to learning how to spend less rather than figuring out how to make more.
"Never assume income and retirement are tied at the hip," Adcock writes on his blog, ThinkSaveRetire. "It is almost always easier to retire early based on a high level of savings than a high level of income."
That's because the more you earn, the more susceptible you are to lifestyle inflation, Adcock explains: "The more we have, the more we want, and the more we want, the more we spend. The cycle is wicked, and it is nearly everlasting."
When it comes to early retirement, it's not about how much you make. "Can you retire early with a huge income? Of course," Adocock notes. But income "is no recipe for success. ... Your lifestyle is what dictates the magical date for retirement."
It was only after the Adcocks designed a more cost-effective lifestyle — they cut back on their day-to-day expenses, sold their cars and possessions and traded in their 1,600 square-foot house for an Airstream — when they started to see success.
The lifestyle changes allowed them to bank 70 percent of their combined income. But the couple didn't stop there. They invested their savings.
After all, "Just saving doesn't get you rich," Adcock tells CNBC Make It. "That's definitely a good start — you do need to save — but what gets you wealthy is investing that money."
In short: Design a lifestyle that reduces your expenses and maximizes your savings. Then, put your extra savings to work.
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Don't miss: This couple retired in their 30s and are now traveling full time in an Airstream
