Make stuff up, same as now. ;')
Used to do a lot playing around with it when I was younger, and I can tell you there is going to be money made writing news books incorporating these...and all the software to modify...Most astrologers don't make things up out of whole cloth the way you might think; it's self-consistant within a scheme of symbolic reference, based a good bit on the old ptolomeic models and the classical 4 elements of earth, air, fire, and water, and the symbols associated with the mythologies of the names of the planets...and now this just adds a new level to consider...If I was still playing around with it, it would be fun to watch the fireworks...or write some of the articles, but I don't do that any more...I suspect some people are already thinking about what they can do...especially with Ceres being given an upgrade...
I have a perverse mind.