How do the ancient Greece chose leaders?

They didn't have leaders for the entire country each city-state was ruled independently Each polis(city-state) had to chose a type of government I know three( i think that's all)

  1. Democracy- all the citizens (men) get to vote (at least 18)
  2. Oligarchy- 30 experienced and at least 60 year old man belong to the assembly, but two most powerful kings can rule
  3. Monoarchy- a king or a queen gets to be the head chosen by experience, age and power

Hope this helps :)