
22 in.
Psalm 127:3

If you have not been doing these things already, they are the first steps to reducing your grocery budget.
Once you have those down, start checking the weekly sales at one grocery store. My favorite store is Publix. Why? They're coupon friendly, run great sales, keep the store impeccably clean, and have incredible customer service. Their motto is "Love to Shop Here, Love to Save Here" and they've managed to make it true! We have two other stores in the area, but one is not coupon friendly and the other does not seem particularly clean, and neither of them can touch Publix's customer service, so I generally just stear clear (unless they're selling chicken for $2/lb or something like that.)
SouthernSavers.com is an incredible resource for those in the southeast. Each week she matches store sales with the coupons currently available (including links for printable coupons) and posts a list of the "best price" deals at each store. You can click on the products you want to buy and print a shopping list. It's great! (And easy!) Pull the coupons you need from your organized collection based on the list you printed, put them in an envelope or something else small, and head to the store.
When I see products in the Publix sales flier for less than I would spend at Aldi for the comparable product, I plan to buy as many as we'll use in about 2 months. By doing this, my pantry is well stocked with the ingredients I need to feed my family our standard recipes (i.e. pasta, rice, spaghetti/alfredo sauce, baking supplies, canned tomatoes, canned/frozen veggies, chicken, mayonnaise, peanut butter, olive oil, salad dressings, cereal, M&Ms, etc.) On a weekly basis, I generally buy dairy products, produce, a very few recipe-specific ingredients, and then whatever items happen to be at stock-up price. (Among other things, this week I stocked up on olive oil and spaghetti sauce, last week it was cereal--both weeks I spent about the same amount for produce and pantry items at Publix.)
One final word about Aldi vs. Publix. Aldi's prices are generally about 40-60% less than Publix's prices for comparable products. Which means that if Publix is running a B1G1 sale, it will probably be about the same as Aldi's price on the comparable item. When you add a coupon on top of the sale, it's almost always cheaper than Aldi. So, I buy produce and shop the sales at Publix (along with buying whatever ingredients Aldi doesn't carry.) But shopping at Aldi is already about equivalent to saving 40-60% on my Publix grocery bill.

Snuggles are nice. :o)
Once you have a means of organizing your coupons, it's time to start collecting them.I clip coupons for ...
For personal hygiene products, we're a bit brand loyal on deodorant, so I only clip the coupons for those brands. However, I'll take whatever body wash they want to run a good deal on, so I generally clip all body wash coupons, regardless of brand.
When do I sort my coupons?
(My laundry basket has born ample testimony to that fact!)
However, this Saturday, while Mommy and Hannah went to the Ladies' Brunch,
Daddy decided it was time to bring in the big shovel while Matthew napped. 
Definitely beats using the kitchen stool. 
I can put all the categories I want for my coupons in it, it's SUPER easy to file my coupons, and all I have to do to find a coupon is pull the folder and flip through a small pile of clipped coupons. And when I pull expired coupons, my pile to flip through simply gets smaller. A good thing.
I rarely take my black box to the store or even in the van. My black box sits under my desk. When I'm preparing my grocery list, I pull the coupons I need and put them in my smaller pink holder. Since it has a limited number of sections, I simply consolidated my categories.
Have I ever missed a random deal because I didn't have all of my coupons with me at the store? Yes. And I'm okay with that. :o) Since I'm often shopping with three children, and rarely without at least one, I simply have not a spare hand nor room in my cart for my black box.Next week I plan to cover Clipping Coupons ... which coupons do I clip, where do I find them, when do I clip them, and how do I sort them?
What method of keeping coupons has worked (or not worked) for you?