As someone who appears on stage as my job, and as someone who has done technical setup for loads of live events like this, here’s my biggest tip:
Give the sound technician their own microphone!
Nothing is worse than the sound tech having to shout from the back of the room when setting up. Actually there is. Worse is when something goes wrong on stage during an event, and the audience is loud, and the people on stage have no way to hear the technician telling them to use the spare microphone or to move to another part of the stage, or any number of other solutions to a technical problem that would be easy to fix with easy communication from the sound desk.
Actually, there is something worse than that. The worst thing is to have the sound technician talking into some coms headset and another technician on stage with a headset listening and passing on any message to the speaker, and then relaying messages back from the speaker on stage to the sound technician. It’s the biggest pain in the ass ever.
If there’s a lighting or video technician, they should probably have a microphone too. That’s not always possible, but everyone being able to talk to everyone else and hear everyone else without going via coms headsets is the single thing that makes my tech setups run literally 20 minutes shorter than doing things via onstage technicians via coms headsets.