Just finished episode #2. So far it reminds me a bit of the "The Mandibles: A Family, 2029-2047" although with a slower build towards crisis in terms of story-telling.
Having not seen the rest of the series yet, I don't know how bad things will get. Based on how things are where I am right now: diversification.
1) First, remember that, while it may drop a lot and stay low for a long time, in the long term the stock market isn't going to go to zero short of a Mad Max/Waterworld type scenario where we'll all have far worse things to worry about (or a Star Trek type scenario where we stop using money and won't have anything to worry about). The stock market in Germany survived both hyperinflation, the death of two currencies (the Mark and the Reichsmark), losing two major world wars, and a subsequent occupation.
2) On the other hand bank failures and bank runs certainly do happen. It's good to have accounts with at least a couple of institutions. Historically FDIC insurance usually only takes a few days to kick in if the bank you have your account with fails, but in a major crisis it might be longer so it's good to have alternatives you could tap to cover living expenses if you couldn't access your primary bank account for a couple of weeks or even a month or two.
3) Don't hoard cash (in the bank). I'm bad about following this one myself although a lot better than I used to be. Leaving aside the issue of bank runs, cash is also losing value to inflation constantly. Given what I've seen so far in the show my guess is that we see hyperinflation sometime in the next four episodes.
4) Now to flip that around, do keep SOME physical cash around. Again, this is a buffer against problems accessing your bank account, but it's also great for power or internet outages that shut down credit card readers. Common in hurricanes, ice storms, earthquakes, and now in California whenever it gets dry and windy enough to make PG&E nervous.
5) Blend in. Avoid ostentatious displays of wealth like fancy cars/clothes/houses (FIRE makes this a lot easier for many of us). Don't live in the "rich" part of town. Just come across as part of the 99% (or 90% or 70% or 51%), not the 1% (or 10% or 30% or 49%). When people feel like they have no money, no options and no hope that tends to boil over into protests and riots and mob violence. You don't want to be a the sort of person who'd be targeted. <-- this hasn't shown up in the show yet, but might in the remaining episodes.
(So far the show is pretty griping although also kind of depressing.)
