How To Talk To A Woman Who Is Wearing Headphones:
Assess the situation. Due to wearing headphones, is she unaware of immediate danger, such as a fire, an active shooter, a speeding car with no breaks, or some other threat?
If "yes," do everything possible to get her attention. Wave your hands. Yell. Anything... you're there to save a life, after all, so it's okay to look like a fool.
If "no," then leave her the fuck alone, you desperate, intrusive asshole.