Quick answer - if you’re using Gig Performer, it’s pretty trivial.
I never used side chaining myself. In fact I wasn’t even sure what it was for a long time. But I got forced into find out a few days when a potential customer asked if it was possible to do side chaining in Gig Performer. So I read up on it quickly and (as those of you who use the technique know perfectly well), it’s a way to control the effect on one stream of audio using a different stream of audio. A very popular use for side-chaining in EDM is to “pump” the audio level from a bass drum.
Turns out that in a traditional channel-strip based model, setting up side-chaining is complicated. You have to create extra aux channel strips and send the control audio over to it, make sure it doesn’t get mixed into the output, then you have to configure your plugins to tell it the bus number for the side chain input.
Watch this 3-minute video to see how easy it is to do side-chaining with Gig Performer