I'm far more often annoyed than delighted by previous readers' marks in used books, so I assume that my notations will be equally annoying to future readers, and avoid making them.
Acting still rings my bell as much as it did in high school. Plus, I can now indulge my interests as a producer as well. My work is more fun than fun but, best of all, it's still very scary. You are always walking some kind of high wire.