If the terminals are not polarity marked then they can be connected without concern for the input supply polarity.
For parallel operation one side of the supply is connected to the same terminal on each capacitor the other side of the supply to the opposite terminal.
For series, one side of the supply would connect to one terminal of a capacitor, the other terminal would connect to the second capacitor etc.
This show it diagrammatically.
They appear to be AC type motor caps.