There are several levels to this: everything from eating right to exercising to exercising basic hygiene to going to doctors' appointments, and the like.
That's not what I'm talking about.
What I'm talking about is making sure an individual can take care of themselves. Odysseus covered some of it in his financial advice columns, but I want to expand on it a bit.
First off, and this is the most basic part, the individual must make sure they have a job. It would be better should that not be a minimum wage, part time, dead-end job (though there are actually fewer of those than most believe, given how hard Casey's tried to get Odysseus trained on everything, and to promote him), but any port in a storm. A job equals income. And even a part-time job that pays minimum wage is liveable, if you're careful. And it grants the time to go seek out a different job that offers more hours and/or pays better. Or, failing that, a second job.
Second, start a savings account. A few dollars a week until a grand is saved up is enough to start. That prevents an emergency brake repair from wiping out everything someone tries to do to better their lot.
Third, should that aforementioned job happen to be a part time, minimum wage job, the next step is that the individual in question should stop indulging. No more eating out--not even from the McDonald's dollar menu--no more coffees that they don't make themselves, no more money spent on frivolities. Why? Because the average American is an idiot, and carries a metric fuckton of debt, between what they took out for college, what they owe on their car, and what they owe on their credit card(s) and/or payday loans.
And, once the individual stops indulging in whatever little habit tends to suck the money out of their bank accounts, they can start paying down those debts.*
Getting rid of those debts makes everything else easier.
Fourth, pay cash or do without. On everything, basic medical care included, because a yearly doctor's visit isn't too expensive, if it's budgeted and saved for. And no, having someone else pay for medical insurance isn't a basic, human right. Neither is steak, or junk food, or cell phones of any type. Or internet. Or cable.
Fifth, a solid pantry, holding a few weeks' worth of food (enough to get through a short-term emergency or unemployment) should be assembled. I recommend a membership at a warehouse store--it makes acquiring things in bulk a lot simpler...and a lot cheaper. I think we save somewhere around a thousand dollars a year on the groceries we get at Sam's Club. When the kids were in diapers, it was more than that.
I think the biggest thing, the thing that makes the most difference in being self-sufficient is the capability to plan ahead and to defer gratification. And both are involved in each step of taking care of yourself.
*I recommend Dave Ramsey's plan for that. And no, I'm not being paid to say that. I was incredibly disappointed when our local talk radio replaced him with Sean Hannity, who annoys the piss out of me.
57 minutes ago