There are many possible ways to go about it, but as a side bit of reading, Scott Santens puts together one very reasonable set of ideas as a start on how to pay.
That “reasonable set of ideas” basically restructures the entire Federal Budget in order to provide a UBI that amounts to less than half of what people say is a “living wage”. (15K an hour).
So, not so reasonable; it runs into the same problem that Jindal ran into in Louisiana and that Brownback ran into in Kansas: the structure of the budget and the tax code becomes ingratiated into the fiscal behavior of the companies and the citizens. They arrange their businesses and financial affairs AROUND those items. So, changing anything must be done on in an evolutionary way, otherwise you end up crashing the economy.
But, then, there’s also political and economic reality to deal with. It goes without saying that the current political structure would block any such sweeping proposals, and the demographic reality is that the voting block which is of retirement age and above will continue to grow until 2045.
And even if such a proposal would somehow be miraculously passed, it doesn’t take into account capital flight.
I really don’t know why people spend so much time on Medium debating UBI. There is a far better chance of a UFO landing tomorrow than UBI actually being implemented.
And then the larger question is “WHY”? As of today, there are many jobs not requiring high levels of education that pay well that remain unfilled, most in the trades and allied health areas. Yes, there may be a day in the latter half of the century when automation has destroyed so many jobs that something akin to a UBI becomes necessary, but nobody who is alive and debating the matter today will still be alive when it finally becomes necessary.