I always find myself halting around action scenes. I might be able to do the build-up to the action, but when it comes to the actual start of the action, they just don't play out well enough in my brain. I always find myself in a dilemma about the best place to start. for example, my current protagonist is unknowingly heading towards action scenes with zombie-like creatures she doesn't know the existence of. and although she wouldn't be in the action directly, she'll be a witness while a companion of her's fights. I can't figure out how they would begin. any advice?