First we are going to sit down with all members of the household and are going to brain storm as many possible disasters, emergencies, and scenarios as you can come up with. Everything from a broken arm to the zombie apocalypse. I specifically include the silly and impossible at this stage because it makes it fun for the whole family. They all compile on to one giant list. At this stage do not get wrapped up in any sort of plans or impacts. Think of movies, books, tv shows, and how they could apply to your household. From the big to the small, flat tires, and other mishaps. Internet outages or disasters that could impact you indirectly are also good ones to add at this stage.
Now we are going to sort the list based on a two factors. Probability and Impact. Set a time line for your plan, I recomend a period of 3 years out as that's about how long preps take to build and be recycled. So for each item in the master list, we assign it a score. 1-10 of "how likely is this to happen in the next 3 years" and 1-5 "how much of an impact will this have" So while laser wielding zombie dinosaurs may still have a major impact, the likelyhood of it happening is extremely low. This is going to give us a list of the most likely and most impactful events, customized to your household. This is also a good time to condense duplicates. Godzilla and Deep Impact, basically have the same end result so really can count as one.
With each scenario on our list we are going imagine the scenario as fully as we can, and try to imagine all the resources you might need for that scenario. We will eventually come to a list of all the needs for each scenario. So let's start with a simple one: Emergency Room visit. The needs are things like:
Each need gets the threat score for it's relative scenario, then you combine all the instances of that need together and add all the scores. This will rank the needs based on both how many different scenarios it will help mitigate and the severity of those scenarios. Things that are more useful will filter to the top of the need rank. The higher the score, the more the return on investment of the mitigation.
Now that we have a list of the most common needs, we start addressing each one with a mitigation. This is where the more classical "prepping" comes into play. But instead of making a plan for a specific scenario, you make a plan to deal with the specific impacts of many scenarios. Using the Emergency Room visit above:
These Needs and Mitigations would hardly be unique to this scenario and many of these would be the same mitigations applied to simmilar needs in other scenarios. By addressing the individual needs, we can make a flexible plan that works for 100's of scenarios, because life rarely will fall directly into the boxes we define for it.
Once you have your mitigations in place, it is time to test them. Instead of imagining some made up scenario and trying to sandbox it, we are going test them live. Take the list of impacts, and pick 3-5 at random. Now you have to live with those impacts for the next 24 hours, relying on the mitigations you prepared. So say you draw No Power, No Water and No Transportation. Well, time to go throw the master breaker and see what all can run on the generator, turn off the water and use your bottled supply, and plan to use Uber or walk. Draw the evacuation card? Go to a hotel with only your go bag. The biggest strength of this method is you can test it without having to play pretend, just dealing with life using the mitigations you prepared.