I go to the store, on average, a couple times a week. Once for a big shopping trip, and usually a second time to get fresh veggies and meat for later in the week.
Some of you are going to think this is weird, but I shop completely backwards from most people. The only list I take is for non-consumables like soap, paper towels, water softener salt, and so on. As far as meals go, I do very little planning ahead. DW and I have worked it out where we have 5 nightly meals at home per week. The other two nights we eat out. Two of the sit-down meals are usually vegetarian.
So what I do is take a notepad with me to the store and jot down numbers 1 through 5 - one number for each meal. Then I walk to the meat & seafood area of the store see what's fresh, looks good, is on sale, etc.
Whatever I pick up there is generally what I plan meals around. So I write each item next to one of the numbers. Then I head back to the produce and dry goods sections and get the sides and veggies to go with the meals. Sometimes I'm surfing the net for recipe ideas while in the store.
I know. It's bizarre. But I've been doing it this way for over 30 years now.