If you want to save big, you have to know where your cash is going in the first place.

Many early retirees started their journey to financial independence by analyzing their spending habits and figuring out where they could cut back. “Knowing how you spend lets you determine whether you get value for your dollars, and where you might be able to focus efforts to reduce expenses further,” says Justin McCurry, who banked more than $1 million in a decade to retire in his 30s.

Try tracking your purchases in a spreadsheet or use an app like Mint, You Need a Budget or Personal Capital.

Automating your financial life — or sending your money directly from your checking account or paycheck to investment accounts, savings accounts and creditors — is a popular strategy among early retirees and super-savers.

“It stops you from sabotaging your own progress,” says 26-year-old Richard Meadows, who banked $100,000 in three years. “If you run out of willpower and you blow all the money that you meant to save on a big night out or new shoes that you didn’t really need, then you’re never going to get anywhere.”

However, if you automatically set aside money in a retirement account or for bigger savings goals like a home or car, you’ll never be tempted to skimp on savings.

Early retiree Chris Reining, who built a $1 million portfolio by age 35, will tell you that the key to saving half your income is to start with the small stuff.

“I know there are some people out there that say you shouldn’t worry about the $5 latte, but the more I think about it, cutting out the $5 latte was a good place to start,” he tells CNBC Make It. “Because if you try to downsize your house, get rid of all yours cars and make all of these drastic changes, it’s so overwhelming and you’re not going to do any of it.”

After foregoing his morning coffee, Reining eliminated the $15 lunches he bought every day. Next, he cut out the bigger things, such as the $1,000 a month he spent flying airplanes. “The small changes will lead you to be able to make the big changes,” Reining says.

“If you’re not measuring something, then you don’t have that feedback loop. You don’t know whether you’re heading in the right direction,” says Meadows, who tracks his net worth with a custom spreadsheet.

He’s in good company. Grant Sabatier, who went from having $2.26 in his bank account to $1 million in just five years, says a crucial step he took was monitoring his net worth: “I look at my net worth every day when I wake up in the morning and have my morning coffee. There are few greater motivations than seeing this number rise over time. No matter where you start from.”

You won’t get very far without the right mindset. Commit to saving big starting now.

It worked for Matt of “Distilled Dollar” and his fiancee. The Chicago-based couple saves 60 percent of their income and plans to be financially independent by age 35.

“We stopped a nasty habit we had of reading about great tips and then failing to implement them,” Matt writes on his blog. “Avoid our mistakes. … Literally, do something today … and start saving money.”

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