Courtney Jespersen knows a thing or two about saving money. She’s a retail expert at NerdWallet, a personal finance website. We tapped Jespersen for ways to save this back-to-school shopping season. Here are her tips.

Set a budget ahead of time

“If you don’t keep track of what you’re spending, before you know it you’ve spent more than you set out to,” Jespersen said. “Really sit down and make a budget — how much you’re willing to spend.”

Take stock of what you already have

“You get a list of supplies you need and you feel like you need to buy everything on the list,” Jespersen said. “It’s important to look around at what you have at the house already — more often than not, you might already have some of the things on the list.”

Compare prices

“I like price matching — it’s a great way to save,” said Jespersen, adding that Staples, for example, has a price-match guarantee. “Do your homework.”

Buy in bulk

“If you know you’re going to use tons of pencils, it can make sense to buy in bulk” at stores like Costco or Sam’s Club over an office supply store, Jespersen said. “You’re paying more for the larger pack but generally lowering your unit price.”

Look for student discounts

For students heading off to college, take advantage of that .edu to save on tech. “Best Buy, Apple, Dell — they have education pricing,” Jespersen said. “It’s as simple as signing up with your university email address.”