Step 1- Figure out what days you are making something and if there are any stipulations (fast, late, etc)
Step 2- See if there are any meals you forgot to make last week (it happens, don't worry) or food that's nearing the end of it's shelf life (do the float test for any eggs, please, don't guess)
Step 3- Go through your favorites/pinterest board(s)/recipe books/recipe box and pick out recipes you like and fit your time. Keep in mind how many servings each recipe makes for your household (generally with DH it's 2 for every 3 it says in the recipe depending on the source, my Scandinavian cooking books tend to be closer to 3.25 for ever 3, go figure)
Step 4- Spell out all the ingredients of each recipe. Then eliminate those you already have on hand.
I didn't do it here, but list what kind and how much of each ingredient
Step 5- Look at what you need beyond what is needed for the preplanned meals
Step 6- Combine all meals into a department by department list (try and list them by how show up in the store, I can do it for HEB and Harris Teeter but still can't get Trader Joe's). Remember to mark how many you need, and if you need it for more than one recipe
Step 7- print, email, whatever. Make sure you have it at the store.
*I'm not kidding, and this is before I knew him or he would have gotten my "disaproooval" face.