In our household, I've found the way we spend money on what we put into our mouths reflects how we spend in other aspects of our lives. When we first got married, our meals were rushed, disorganized, and not planned out. As we got settled into our daily routines of marriage, I decided I really wanted to make a plan for our suppers. I hoped that if I invested a little bit more time into what we ate, I'd lose at least a little of the stress associated.
I was so pleased to find that is EXACTLY the way it worked out. I went from getting home after work and immediately stressing about what was for dinner, to knowing what we were going to make, what goes into it, and having all the ingredients needed on hand. Of course, exceptions were made, when I was pregnant I was an extremely moody eater, and had sudden aversions to foods I previously enjoyed (bacon), but for the most part, I find a meal plan pretty easy to stick to.
When you're planning your meals at the beginning of each week, that means your grocery shops will be planned. Which means you know pretty much exactly what you're going to spend. This change virtually eliminated impulse shopping for us. If it's not on the list, we don't buy it, and if we left it off the list, it was probably for a good reason. We don't just shop smarter, we shop HEALTHIER now, and we generally only shop once a week.
Ted, being Ted, took things up a notch and made me an excel spreadsheet of all the foods we usually buy, divided into sections of the grocery store, with the days of the week typed out at the bottom. I can write down lunches and dinners for the whole week, then after our shop post the whole thing on the fridge. Things like cookies, baked goods, and pizza pockets don't exist on the spreadsheet, so they don't make it into the cart.
I found that being organized with making a meal plan and a grocery list was a first step to financial organization. It's a small and really important way of being responsible with the things you've been entrusted with. It was a great lesson that sometimes one small change can lead to a whole bunch of other small changes, that turn into a bigger picture kind of change.