So this article is entitled: How I stopped worrying and learned to love Chaos.
No matter the trigger, the main thing to look at right now is the economy. Those of us not old enough to remember the depression usually think; BOOM, Stocks crash, bank holiday, Great Depression. Actually it took a few years to go from point A to minus point A.
So how best to be prepared to ride it out? If you are into sustainable living, you are probably also into self-reliance. That is a great start. You may even already have stockpiles of food, fuel, and other needs in case of a disaster. Those are needed for short term, what about during some kind of stabilization?
Odds are you will lose your job. Not much need in Aerospace Enginneers in a depression. Salesman? Well, if you have something to sell that someone wants bad enough to buy with what little they have. What kind of jobs, and the skills you will need for them, would allow you to survive?
Survive, there is a keyword. Let's look at primary survival requirements.
Air: You can only last minutes without air.
Shelter: You will only last a short time in extreme weather without shelter.(Clothing is portable shelter)
Water: You will last a few days without water.
Food: You can last a week or more without food.
Now let's look at the Modifiers, which modify how you will act to the Primary Requirements.
Health/Wellness: Necessary to be healthy and take care of injuries/illness to be able to survive.
Alliance: You can't do everything yourself. Need Family or Friends, someone else.
Resources: What is available for use?
Using this list as the basis, here are some job/skills that will allow at least for barter, if not a job.
House Construction - Mainly for creating basic shelter, alternative methods, inexpensive methods best.
Farmer - Producing food.
Hunter - Providing meat.
Rancher - Providing meat.
Herbalist - Using herbal knowledge to help keep people well.
Repair - Too expensive to replace, have it repaired.
Sewing - Again, new clothes too expensive, have it repaired.
Cook - Providing a service cheaper than a restaurant.
Mechanic - Repair to keep it going.
Going further:
Blacksmith
Medic
Tanner
Butcher
Weaver
Shoe Maker
Carpenter