Actually, the paying part is simple: all taxes as sales taxes, with a prebate/minimum income. By far, the biggest demand for excessive government comes from the consumption of resources and all of the “security” demands caused by people not knowing the true cost of anything.
As for who 'decides' anything? The first step is informing people at the point of decisions: the checkout.
After that, there should be a minimum public service required for everyone, and as many political offices as practicable should be random lottery, just like jury duty. If people aren’t forced to participate in the bureaucracy, then exploiters will make it a profit generator that consumes them.