Millennial who saved up to $3,400 a month to get out of debt says this mentality helped her spend less

Guen Garrido paid off nearly $70,000 worth of debt by picking up a side hustle, limiting her spending and adhering to the debt repayment strategy popularized by money expert Dave Ramsey: the "snowball method." But the 32-year-old also became debt free by changing her mindset, she tells CNBC Make It.

Specifically, she says, “I focused on being grateful for what I already had.” And it helped.

"Especially in this day and age, with social media, you compare yourself to other people — you see where they are traveling and what they have, so you are tempted to compete with them and have the same things and buy more things,” Garrido says.

Indeed, as one study found, social media can have a significant impact on spending habits, particularly those of millennials: 90 percent of millennial respondents said social media creates a tendency to compare their own wealth or lifestyle to that of their peers.

About 60 percent of young people reported feeling "inadequate" about their own life because of something they saw on social media, like gadgets or vacations. And, as a result, 57 percent say they parted with money they hadn't planned to spend.

Even more alarming, about 40 percent of millennials are going into debt just to keep up with their friends.

Over the three years and three months she spent tackling her debt, Garrido put an average of $1,800 a month towards her debt payments and once even made a monthly payment of $3,418. Her advice for anyone who wants to save more and spend less is to focus on being appreciative for what you already have: “I found that, when you put yourself in a place of gratitude, you feel content and you don't have to have all that stuff and then you just work on yourself.”

Derek Sall, who eliminated $116,000 worth of debt before age 30, agrees. For him, the key to saving money started with changing his mentality and realizing that he didn't need to keep up with the Joneses.

The No. 1 way he found to avoid comparing his situation to anyone else’s was to avoid social media altogether, he tells CNBC Make It: "The best tip I can give is just live your own life. The best way to just live simply and be content is just to turn it all off and hardly pay attention to it at all. Because that's what gets people in the most trouble. They see, 'Oh, my friend went on this great vacation, and I wish we could do that!'"

Like Garrido, he focuses on how full his life is without new and often unnecessary things. "It's easier for me now, just realizing how much fun I'm having without having all that stuff," he says. "I don't call myself a minimalist, but I realized that the more and more stuff you have, it almost makes you less happy."

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