One of the great attractions of the Alarishi Empire is that almost anyone can establish their own local government and set up their own laws. The chartering process is straightfoward:
The Empire owns all existing real estate, so if you want an asteroid hab, you need to lease it from the Empire. If you build an entirely artificial habitat, such as a starship, then you own it and that can be your territory.
The charter of government is essentially your constitution. It specifies how the executive, judifical and legislative authorities are chosen, and it spells out the process by which laws are made and enforced. It can be as simple as "I, Jack Old Ron, am sole authority of the sovereignity occupying the asteroid [designator] and a 40,000km radius from its center of mass. Any transgressions against my whim are punishable by whatever level of force I choose to employ against the transgressor. If I am deceased or otherwise incapacitated, Sue Lai of Han Bank shall be acting executive. The sovereignity shall maintain warning beacons to advise space traffic which may approach our active defense zone." Of course, that sort of charter will not attract many immigrants, but it is valid.