Next to the rent or mortgage payment, food is likely your biggest household expense. And have you noticed food prices steadily creeping into the stratosphere? A little here, some more there doesn’t seem too bad until you get through the checkout. Wow, $100 doesn’t go so far these days! But you can make it go a lot further if you will diligently stick to a few sage guidelines.

I won’t say these are new ideas. In fact, these are the things we learned from our grandparents—especially those who lived through the Great Depression! It’s good for us to remember what we’ve learned in order to stay sharp and resolute.

No. 1: Don’t shop hungry

Studies find you will spend at least 17 percent more for the simple reason that everything in the store looks so good!

No. 2: Shop with a list

Get tough on yourself. If it’s not on the list, it doesn’t go in the shopping cart. Even if you see all kinds of great “bargains” you didn’t know you needed before you saw them, stop and think. Then walk on by. If it’s that important, you can come back later.

No. 3: Prepare your list

Make your list at home using the store’s weekly sales ad. Build your menus around what’s on sale. As far as possible, buy only what’s on sale. Make do. Get creative.

No. 4: Concentrate on the loss-leaders

These are the items that are deeply discounted to lure you through the doors and into an impulsive shopping mood.

No. 5: Know your prices

Keep a written record of the regular per-unit prices of the items you buy most often so you’ll know whether a special is a bargain. Many times, specials have nothing to do with a sale but more to do with a marketing campaign.

No. 6: Buy in season

Fruits and vegetables will be the best quality and the lowest price when they are in season.

No. 7: Shop with cash

Take only the amount of cash you have decided to spend on this trip. Leave the checkbook and that wallet filled with plastic at home. If you come across a fabulous bargain and don’t have enough cash, you can always return later with more cash to stock up.

No. 8: Carry a calculator

Keep a running total of your items in your cart so you can keep track of where you are and to avoid checkout embarrassment.

No. 9: Shop at larger stores

Because of volume discounts, larger stores are generally cheaper than smaller ones.

No. 10: Find a bakery outlet

These kinds of thrift stores offer wonderful bargains. But be careful. It’s easy to spend more on all those bargains than you would have on full price items at the supermarket.

No. 11: Use coupons

Buy the smallest size the coupon allows to get the greatest savings.

No. 12: Consider generic and store brands

Many times, the product is identical to the brand name except for the lower price. If you are unhappy with the product, return it to the store for a refund. Yes, grocery stores have refund policies.

No. 13: Shop solo

Being distracted can be very costly. Leave the kids and spouse at home and you’ll be more laser-focused.

No. 14: Don’t buy nonfood items at the grocery store

Housewares, pharmacy items, greeting cards, paper goods and cleaning supplies can be purchased for less elsewhere: dollar stores, and discount department stores like Target and Walmart.

No. 15: Avoid individual-size packages

Buy the big bag or size and divide into smaller portions at home.

No. 16: Avoid convenience items

It’s more cost-effective to make your own salad dressing, chicken-coating mix, soups and so on.

No. 17: Learn sale cycles

Study sale flyers until you recognize predictable cycles. Buy enough when it’s on sale to last until the next sale.

No. 18: Use it up

If your garbage disposal and kitchen trash have become the best-fed members of the household, stop throwing so much food away. Prepare less, and if you still have leftovers find creative ways to use them up.