Welcome! Just a couple off the top of my head
- when you start your feed, think of it as the start of your show. Don't be wandering around, setting up, bs-ing. Start talking and engaging right away as if you're welcoming them to your show. Think if you turned on some tv show and the actors were wandering around not giving you anything. So from "action" you're on stage.
- On that thought, consider this a performance, not a training session. Personal training and group instruction are completely different. This is a performance, it's the YOU show. It's also a class so you should be teaching and not just working out on camera. What do you want your people to come away with other than just sweat and gains? Be an educator, trainer, and performer.
- People learn 3 ways: Visual, auditory, and kinesthetically. So yes showing the is important so you must do the movements with them, but also speak on what you're doing and why. Then for the kinesthetic learners (this is tough virtually) put your hand on your body and invite them to do the same. Have them feel their muscles working. Or use whatever you think is good. Just remember not everyone is going to learn just by watching you.
Don't expect to get all this by next week. I've been training and teaching group fitness for the last decade and it's taken me a while to get the hang of it. But it's a fun gig. Just remember to perform and to add value every chance you get.