Just as Social Security is structured as social insurance that we buy, the UBI should be structured as a dividend. The UBI is what we pay ourselves for being such good citizens of a place that can print money because its citizens are so good. Call it a distribution of the benefits of exorbitant privilege.

The dividend concept points the way to the implementation. Dividends are taxable. Just give people a $12k tax credit and require that they report an additional $12k of dividend income. Then make any resulting negative balance refundable. For those with jobs, reduce withholding. For those without jobs, advance the money through a welfare-like system and reduce the tax credit accordingly. Because the payment is a dividend, it would not be means tested beyond the applicable tax rate.

Additional benefits for children would not be UBI dividends. They should be subsidies for child rearing, tax-free but subject to phase-out. I believe that "integrating" such payments would muddy the waters.

I don't understand the economics of wage subsidies. My default position is a higher minimum wage that gets funded by higher prices if necessary. But I would be open to wage subsidies if Coasian bargaining didn't make them just employer subsidies.