Supermarkets are designed to mess with your mind. I believe firmly that they are designed by a room full of middle management folks, sitting in an office somewhere with their coffee and suits, chuckling over the tricks they’re pulling on the populace. Stores are often organized so that the most commonly purchased items are on the far side of the store from the entrance, so that you’ll have to walk past lots of frivolous items to find the things you’re looking for. As “good” consumers, we often find ourselves buying several things we don’t need as we walk past them.

The trick to visiting a supermarket and avoiding these impulse buys is to avoid them as best you can, and the best tool for this is to make a shopping list before you go and stick to that list. With a list of items you need and a desire to only get items on your list, it becomes much easier to cut down on those impulse buys.

For me, the worst impulse buy was a pint of Ben & Jerry’s ice cream. It’s a delicious, insidious little snack at a convenient price point that I would always pass by on my way to get milk or something else that I actually needed. Unsurprisingly, before I went with a list in hand and a goal in mind, a pint or two would always find their way into my cart. Now, if I get a strong desire for Ben & Jerry’s, I add a pint to the list, but most of the time I don’t splurge on it. Not only has it cut some pounds from my belly, it’s also saved me several dollars per store visit.

If you want to invest a little time, I’d recommend making a document that allows you to make sub-lists in general categories based on your store’s layout. For me, that means a “dairy” section, a “frozen foods” section, a “meat” section, and so forth. I use a Word template and print a new one off to hang on the refrigerator each week. This makes it even easier to stick to a list, because you do less searching for each item and thus are exposed less to frivolous items.

Here are five quick ways to build an efficient grocery list that will save you some serious money at the grocery store.

1. Cut your visits down to once or twice a week. I usually do one main visit per week (on Saturdays) and one smaller visit (usually on my way home from work on Tuesdays). This reduces the opportunities to buy frivolous things.

2. Start off each new list with the things you get every visit. For me, that means skim milk, orange juice, and yogurt - I don’t visit the store without picking up these three things.

3. Add things to your list as you discover you’re getting low on them. A good way to do this is by keeping a pad and a pen actually attached to the refrigerator so that it is central to places where you might find stuff.

4. Before you go, consider what you’ll probably eat at home in the next week. You don’t need to sketch out every meal, but have ideas for several meals before you go and make sure you have the ingredients for all of those, plus any additional foods you might want.

5. Check your coupon envelope. If you use a solid, non-intense coupon strategy, you’ll probably save some money for the shopping trip by hitting the coupon envelope before you go and updating your list to match.

The real key, though, is to stick to your list once you’re in the store. It feels like a real accomplishment the first time you see a smaller bill at the checkout and you look through your sacks and don’t see anything silly.