5. Buying the brand

Sometimes it pays to buy brand names, and sometimes it doesn't. The key is to know the difference. Kay says brand buying can torpedo a grocery budget, particularly when prices of staple products, such as milk, are climbing in double-digit increments.

"There are some exceptions, but brand-name buying is not always the best indicator of quality," Kay says. She recommends buying generic at the grocery store and using common sense when it comes to other purchases, such as children's clothes, especially when it comes to items you'll hand down to your younger kids.

"We had four sons, and we could buy two pairs of cheap tennis shoes in six months or one pair of quality shoes for six months (until they outgrew them)," Kay says. She bought name brands when it came to her kids' shoes because it made sense to buy a more durable product. But she buys generic fabric softener at the grocery store to save cash.

6. Getting clearance-sale fever

Even prudent shoppers seem to react differently to clearances, especially after Christmas. If you've ever found yourself the owner of matching 3-foot-tall wooden nutcrackers, you might be a victim of clearance-sale fever. The solution, says frugal shopper Sara Davis of Clayton, N.C., is to shop clearances only when you can match the clearance to your real needs.

Davis says she shops for necessities such as pillows and sheets during January white sales and picks up candles when they're marked down for clearance, because these are items she would purchase anyway. "I don't buy holiday decorations after the season because I don't feel like storing the items," she says. As for things she really wants, Davis stalks those items before making a purchase.

"I once waited two years to buy a pair of shoes I wanted just to make 100% sure they never went on clearance," she says.

7. Taking couponing to the extreme

While reality television has turned couponing into a sport worthy of the Olympics, experts say improper coupon use can drain your finances, not help them.

"Good couponing is not buying something simply because you have a coupon; good couponing is buying something because it's a good value," says Kay. She says it's a lure that can hurt your budget if it leads you to buy a brand that costs more or if you have to buy items in larger quantities, as in a coupon that requires the purchase of two items.

Davis avoids compulsive shopping by using coupons only for items she typically purchases -- a good policy, according to Kay. To make the most of your coupons, sort and match them to your grocery list, then store sales circulars. Download store-generated coupons from the store's website to add more coupons to the mix. Trade coupons with friends to maximize your savings -- keep only the ones you'll use, and pass along the coupons your friends will find handy. Finally, never assume anything is a bargain simply because you have a coupon for it.

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