You can snap your fingers tomorrow, and it’s the day after the revolution, time to sign the Constitution. How does it work?
Assume total creative control, but once it’s written it’s in the hands of the general population. They will eventually twist and distort it any way they can.
ETA: I should have been more specific. I’m looking more for basic structure, not policy. Monarchy, direct democracy, democratic republic, that angle. Should everything be a pure democracy referendum? Should we delegate to representatives? How much power do we give them? How do we delineate governmental strata (nation, state, county, city, neighborhood, etc.)? How do we allocate authority to those strata? How do we divide powers, and how do those powers check one another?

Fair point, hence why I said “or must give you an alternative day off”.
Noise would still be a better problem to have, especially with ranked-choice voting in place, than having millions of people who just didn’t give enough of a shit to bother. At least if it’s mandatory you’re forcing some of them think about how things are going and where they’d like them to go from here, even if they end up just writing in “Mickey Mouse” or some silly bullshit.