You connect a RS232 cable to the base of the HC and connect to that using a USB to RS232 adaptor and the ASCOM driver. Align using the HC before connecting.
BTW there’s a new Celestron ASCOM driver available on the ASCOM-Talk site. If this is used with the NS+ HC version 5.22 or better then the ASCOM Park and UnPark use the HC Hibernate and Wake Up functions. This means that power can be cycled between these and you retain your alignment.
This version uses the HC Home and Set Home functions for Park and SetPark, previous version use separate positions.