This article describes how to set aside extra food in the event you are unable to get to the store for a few weeks or a few months. Or if for some reason your local stores are not able to restock their shelves for weeks or months (ie. earthquake, hurricane, strike, economic problems)
Identify meals you and those in your home enjoy. Identify as many dinners, lunches, and breakfasts you can think of. You may want to keep a record of the meals you eat for a few months to get a better list of meals you enjoy.
Make a list 30 dinners, 30 lunches, and 30 breakfasts that you really enjoy and and can be prepared at home. Give each meal a name. With this list you have a home menu for a months worth of meals. If you can't come up with 30 try 15 of each as a starting place, but try to expand your list to 30 so you don't get sick of eating the same stuff over and over.
Break down each meal into its components that can be purchased at the store. For instance, I really enjoy Teriyaki meatballs over rice. This meal consists of 1 cup rice, 10 meatballs, Teriyaki sauce, brown sugar, onions, and a side of mixed vegetables, and I like to drink milk with it. Once you have done this for each meal add up how much of each item you need to fix all of the meals on your list. If you eat a lot of meat you might find that in your 3 meals you require many pounds of ground beef, several pounds of beef, several dozen frozen chicken breasts, etc. You might also learn that you eat many loaves of bread, many gallons of juice, and milk.
Calculate your food amounts. With your totals for the month calculated now times everything by 3 and you have the makings of a three months shopping list.
Go to the store with this list and try to find the best price for everything on your list. Since now you know what you will be eating you can buy in large quantities and store it at home until it is needed.
Create storage space. You may need to create some space to keep the extra food, both frozen, and dry/canned goods. This may mean purchasing an extra freezer, or some closed storage shelves. Some additional storage ideas are in the tips below.
Start building up as evenly as possible and try to fix all of your meals with things that have been in the house at least a week then a few weeks then a few months.
Prepare for longer food storage. Next longer term storage beyond 3 months needs to be considered. This may include basics such as rice, wheat, legumes, beans, canned meats, more canned fruit and vegetables, sugar, old, yeast, and the supplies to make food out of these things such as a grinder. You may need to obtain the knowledge to use these basic ingredients to make palatable meals.
Stock up on specially prepared foods for long-term storage. Other items to think about are powdered eggs, powdered milk, and freeze-dried meals that come in packages ready to add boiling water.
When freezing bulk ground beef, form it into flat square one pound packages. To make this easier find a square plastic container that holds a pound of ground beef to use as a form. Lay a large piece of plastic wrap in/over the container, fill it full of ground beef, then wrap it up and remove the package from the form. Store in your freezer on edge like books always put new packages on the left and always take from the right for the next meal.
Check the USDA web site for food storage information.
Purchase books about food storage.
Find ways to use even long term storage items so you get accustomed to eating these items and know how to use them if needed.