Get your taxes done using TurboTax

I have just talked to TuboTax support and it turns out I have to mail physical copy of the 568 form, and also get the online waiver.

The confusing part had been that the tax return "printout" PDF didn't include instructions (as I hadn't clicked on the right buttons.) So, went in again (by the trick of "Add State"), then went to the Tools / Print Center and printed the PDF with instructions this time. And indeed, there are instructions for mailing in the form 568.