For the items you buy regularly, determine which local grocery store has the best deals. The same items are often priced differently in different stores.
Even though I never associate Wal-Mart or Target with grocery shopping, I have learned to remind myself to go to these places when I need frozen and non-perishable food. They usually have lower prices than my local grocery stores.
Look out for coupons. There are lots of coupons to be had online.
Sign up for the frequent shopper card at your local grocery stores (not credit cards, but the cards that track how much you spend there). Some deals are for card holders only.
Buy generic brands. There is almost no difference in taste between grocery store generic brands and more expensive brands of canned food and frozen food.
Remember that you don’t have to buy 10 lbs of something if the price tag says 10lb/$10. If you buy 1 lb, they will give it to you for $1.
If you use something regularly, and it is on sale, buy it only if it a non-perishable item or if you can consume it before it goes bad.
If money saving is your only concern, don’t buy organic.
Buy produce that is in season.
If you want a fruit or vegetable that is not in season, buy it frozen. The price of frozen fruits and vegetables rarely change with season, but the price of the fresh ones do.
Don’t go grocery shopping when you are hungry. You will buy extra food you don’t need.