If you use the StudioLive 16.0.2 template when creating a new song in Studio One, . This will setup your I/O so that all tracks 1-16 are feed back to the Firewire return for each channel. You can then use your AUX 1-4 mixes on the StudioLive for Cue Mixing purposes.
To control your Cue Mixes from within Studio One. Create new Stereo Output buses in the Output tab of the Audio I/O setup, (Sub 1, Sub 2 etc) and check the box next to these to make them a Cue Mix. The Sub's will route to the respective firewire return on the mixer. Send these channels to your preferred Aux Out's on the mixer and use the Cue Controls in the Studio One console to route to the Cue/Sub output.
It really depends on your workflow, input channels being recorded vs playback tracks to be sent to Cue's. Experiment with various routing possibilities to find a system that best suits your needs.
https://pae-web.presonusmusic.com/downloads/products/pdf/StudioLiveClassicSoftware_ReferenceManual_EN.pdf
https://pae-web.presonusmusic.com/downloads/products/pdf/StudioLive1602_OwnersManual_EN6.pdf