
Go in with a list. Boring, but it's the whole thing. A list keeps you out of the aisles you didn't come for and gets you out the door before anyone melts down. Even better? hand it to your husband and send him in.

Don't go hungry. You already know this, and you'll ignore it anyway. But an empty stomach is how you come home with two kinds of cookies you really don't like, a few bars of chocolate, and a tray of sushi. Didn't get to eat? Chew sugar free gum while shopping to squelch the temtations.
Buy in bulk, then split it right away. Bulk is only cheaper if it lasts. A big bag of Bisli will just get eaten faster. Portion it into smaller bags while you're unpacking, before anyone wanders into the kitchen. Meat's the same idea: divide it into supper-size amounts and freeze it right away.
Lose the soft drinks. A jug of water with a splash of juice, or just cold water with ice and a lemon, costs almost nothing and empties just as fast at the table. Cans and bottles add up quietly, and they add up even quicker over Shabbos.

Add some funky straws or cups to make it more appealing for kids.
Plan around what's on sale. Check the specials first, then decide the menu.
Buy it whole and do the work yourself. A whole chicken is cheaper than the cut-up pieces, and a side of salmon is cheaper then buying a few slices every week. Five minutes with a knife pays for itself over a month of suppers.

Use canned vegetables when you can. Peas, beans, mushrooms, corn. In addition to being cheaper, you can stock up on those for last minute emergencies.
Use it before you lose it. Roughly a third of the food people buy gets thrown out. Eat the leftovers, freeze things before they turn, and finish what's already open before you crack into something new.
Do one big run. A single stock-up at Shaarei Revacha or Osher Ad beats five little milk trips, especially on the non-perishables. Load the cart with the things that keep, cans, pasta, oil, paper goods, and you're not back in a store every other day grabbing 80 shekel of extras you never planned on.
What are your best grocery habits?