No matter how many times you do presentations, you must be prepared to be flexible. Even if you have a bread and butter presentation, like my standard "Read the book, tell the parents how the idea came about, and then play the magical scale game," each situation may present a different set of circumstances. For instance, what if the event space does not have the equipment you need? What if you are given a skinny space where people in the back may have a difficult time seeing, much less participating?
You may also be presented with a situational opportunity, like how one librarian brought me in specifically to tie into the Lunar New Year. And furthermore, this librarian was NOT interested in my standard presentation, and requested something tailored to craft-making and this Chinese cultural event.
A writer's work is never done. While you are busy promoting one book, you must also be working on that next book, and in between all this you must constantly be on your feet and ready to accept the next presentation request. The thing to not lose sight of is that every presentation is a chance to exercise your creative mind. We will get back to this point again!