Live like you're already poor, reduce all unnecessary spending, adopt an ascetic mindset to support this lifestyle. That way, when a collapse comes you'll be accustomed to living frugally already and you'll have all the money you saved by getting a head start already saved up to get you through rough patches with relative ease.

Now, when I say live like you're poor, I mean do it smart. Don't grocery shop at a gas station, do your necessary purchases in bulk (actually poor people can't or won't, but would be better off if they could.). Don't but the cheapest boots, but rather the best value. But when choosing how many vacations to take, maybe pick camping locally more often than exotic vacations. Eat simple foods, don't order out fancy stuff and get accustomed to such luxuries. Don't automatically buy the latest consumer toy just because it looks fun. Don't move into a nicer apartment just because you got a raise. You get the idea.