1. Shop on Wednesdays. Data from Google Maps show that stores are less crowded on Wednesday evenings. Many U.S. supermarkets also start specials that day, according to Reader's Digest.
2. Look down. Less pricey items are often shelved lower on the rack.
3. Buy whole. From chicken to carrots, buy whole things. If it is pre-cut, it usually costs more.
4. Shop alone. Friends distract, family demands. The kids want this, the spouse wants that. Shop alone and follow your list.