I am assuming you are actuating a solenoid valve.
I am assuming you have verified that the solenoid valve current draw at inrush is within the rating of the PLC discrete output (although this is improbable).
I am assuming that you can live with reduced PLC output life because inductive loads like solenoids are tough on PLCs.
I am assuming you have printed out the A-B manual for the PLC you are using.
In that case draw your circuit diagram so that the + of the 24 VDC power supply goes to the discrete output common on the PLC, and from the output contact to the + of the solenoid valve, and from the - of the solenoid valve to the - of the power supply.
However, I recommend using an interposing relay, so you should wire like this:
+ of the 24 VDC power supply goes to the discrete output common on the PLC, and from the output contact to the + of the relay coil, and from the - of the relay coil to the - of the power supply
+ of the 24 VDC power supply goes to the common on the relay contacts, and from the output NO contact on the relay to the + of the solenoid valve, and from the - of the solenoid valve to the - of the power supply