Every single week I sit down and make a list of all the stuff we need from the various stores. I don't shop at just one. I shop at Walmart for pet products, laundry, plus various other household supplies and some name brand foods. Then I shop at Aldi's for the majority of my groceries and Weis Markets for meats. It's a personal preference and based on the quality of products in my particular area.
It's really easy to find lots of printable weekly menu planners with the grocery list. Here are just a few that are free to download so you can start using a meal planner immediately.
Here's one I created 2 years back.
DIY Home Sweet Home - This one is colorful with the menu planning at the top and grocery list at the bottom.
GlueStickBlog - A really nice looking menu planning sheet included in their 2015 planner printable pack.
Erickson and Co.com - This is a nice planner that includes breakfast, lunch, dinner and snack sections all in a landscape layout.
Once I found one I liked, I printed 52 copies back to back on my printer. You can also save the document to a flash drive and have it printed at a copy shop. After I printed it out I created a quick cover page and printed it out also.
Then I took my printed planner pages and had them bound at my local Office Depot. They even added a clear cover and white backing. It cost a total of $3.80. I love the way it looks and it's much sturdier too.
Here is what mine looks like on a typical week. I cross everything off as I find them and check off each meal as I use them. I don't necessarily eat whatever I listed for the day of the week.
Speaking of the grocery list. I include EVERYTHING that I need to buy for the week on that list. That means food, cleaners, pet food and supplies, paper products, plus any miscellaneous things my family needs that we were able to plan for. If it's not on the list I will surely forget it.
Some people starting out wonder how I know the prices of everything. To be honest I know the prices of 95% of the stuff on my list because I purchase it often. The stuff I'm unsure the price of I use a best guess and I always over-estimate. Once you've been doing this for a couple weeks it will be just as easy for you.
People have asked why I keep all my previous week's lists. I keep them so I can get menu ideas and check prices on items I purchase infrequently. Another reason is to remember what I did when we only had $50 a week or $100 a week to feed my family of 5 if I ever have to do that again.
I really hope this helps you and your family stay within your grocery budget like it has my family.