In 2008, Cherie and Brian Lowe found themselves deep underwater.
Between credit cards, student loans, car payments and a gap loan, the couple had racked up more than $127,000 in debt, but struggled to make a dent in paying it off.
"At that point, we had been married just about nine years and really we just didn't have a plan for our money," Cherie tells CNBC Make It . "We lived paycheck to paycheck, and when a crisis would arise, if we didn't have the cash to pay for it, we would put it on the credit card."
After several failed attempts at taking control, Brian came home one day and pitched a vision to Cherie of what their family's lives could look like without the debt. The couple decided it was time to make a change and they pledged to finally get a handle on their finances. On April 2, 2008, they set out on the first day of a 15-year plan to become debt-free.
But just shy of four years later, on March 28, 2012, the Lowes made their final Sallie Mae payment, conquering $127,482.30 in debt and interest, which Cherie documented on her blog, Queen of Free, and in her book, "Slaying the Debt Dragon: How One Family Conquered Their Money Monster and Found an Inspired Happily Ever After."
To reach the milestone, the couple worked together to both increase their income and pare down expenses. While many larger factors contributed to their success, including building an emergency fund, rejiggering their tax withholdings, taking on side hustles, giving up restaurant meals and living with less, Cherie's No. 1 money-saving trick is simple.
"Every time you check out at the grocery store, you need to look in your cart and find three to five items that you don't need," she says. "You will save $5 to $10 every time you shop without cutting a single coupon."
The tactic works for two reasons: It puts a barrier between placing an item in your cart and actually paying for them and it shaves down your bills little by little.
"It's the pause before you check out that I think is so effective," Cherie says, noting that the idea holds especially true in grocery stores, where it's easy to nab appealing items without much thought about how they add up. "There some things that sometimes we pick up and maybe we might need them next week — and it's fine to go ahead and buy them next week — but right now you probably don't [need it]. Just pause and only buy what you really need."
Few people religiously stick to their shopping lists, and even those who do can often stand to cut back on a few non-essentials.
Cherie also recommends sticking to cash while grocery shopping, which creates another physical boundary between grabbing an item and bringing it home. "It places a firm fence around how much you're going to spend," Cherie says.
Others who have paid off thousands in debt swear by creating boundaries as well. For Lauren Greutman, a former over-spender who dug herself out of more than $40,000 in credit card debt , that meant ditching the plastic for good. "I absolutely had to stop carrying my cards with me, because I was just too swipe happy," she writes in her book "The Recovering Spender." "I had zero self-control."
Even though going cash-only caused Greutman a few embarrassing moments, including the time she forgot her bills at home and couldn't afford to buy groceries, in the long run it held her accountable for her spending and forced her to stick to her budget. "Those boundaries are there to keep you safe," she writes.