You don’t have to do every move and go at a training intensity the entire class. I demo and get movements started in a lot of classes then look around the class at what is happening and cue appropriately. Sometimes I need to go over to someone and correct their movement, etc. I only actually do as much of any one class as I need to do. If the class is going smooth, I rely more on cueing. If it is choppy, I do more demo leading. In the beginning I was probably doing way to much exericsing. Over time, I started to adjust my teaching style and now it is all second nature.