I'm totally on-side with Jim and Hikermor. Start with the basics. Think of protecting yourself from the environment, having water to drink and food to eat, and ways to fix/treat thing when that goes south.)

Stock the pantry with water, long-lasting food, hygene and medical supplies, and prepare to help them last. Gather ways to stay warm, ways to stay dry, and ways to get out of the wind, sun and heat. And start to figure out how you're going to procure this stuff when you run out. (on foot? bike? motor vehicle?)