Cycle stored foods into your meals. Rotate in new shelf stable foods to replace what you've eaten. Spend an extra $5 every grocery trip to go towards sustainability (i.e. 2 cans of spam and a bag of rice).
1. Know the shelf-life of foods; use expiration / sell-by dates as part of your organization plan. Research each item to see how long it will last past the "best by" date (i.e. white rice will last 4 years after expiration if stored properly). Write the throw away date on the product.
2. Stock what you and your family will actually eat. Avoid undesirable foods. However; make some adjustments to ensure you’re also stocking up products with long shelf-lives even if it's not your favorite.
3. Rotate your food stock to your pantry. Eat what you stock, buy more to replenish.
4. Know and use various storage methods; canning (water bathing, pressurizing, pickling), vacuum sealing, freeze drying, dehydrating, storage totes, food-grade buckets & mylar storage bags. Research the best ways to store the food you have (it's usually going to be best in a vacuum sealed package, stored in a cool, dry place away from sunlight).
5. Learn to garden; incorporate it into your food plan. Initially, it can be difficult to develop a sustainable garden. Research, read, and get knowledge from local sources to learn what foods grow best in your environment and soil. Be smart about what you plant. Build a plan that allows for a year-round harvesting of fruits and vegetables. Use what you need; seal (can / vacuum package) and/or freeze the rest.