As you already said, "...teach a man to fish..."

I doubt you can prepare enough to save the masses, unless you are very very rich.

How about buying and distributing a good preparedness / survival book instead? I don't know a good one to recommend because all the books I like are more geared towards wilderness survival. Buying something commercial could get expensive, but you might find free or reduced cost materials from some government disaster preparedness group.

Meet your neighbors, talk to them and get to know them. Then hand them a preparedness book.