Yup, get a good dressage trainer (who doesn't crank their horse's face in towards its chest). With my friend's green 5yo TB I'm not even thinking about headset yet - she throws her head up and hollows out when she's tense and ready to go, so we just get her nice and relaxed at the walk and give her more and more rein til she's really stretching down and out for the contact. Once we have her so she is consistently working in a relaxed fashion and has started to build a topline through long and low, and plenty of nice and loose trot work (she's just coming back into work after a long spell), we will start to ask her to engage her back end a bit more, then a bit more. So long as she's nice and relaxed, her head should take care of itself.
It's about developing the muscles for balance and impulsion, and getting the horse's mindset right (nice and relaxed, confident, focused, and clear in what you want him to do). Putting the head in a "correct" position does not help self-carriage and only encourages the horse onto the forehand.