1. Externalise time instead of tracking it internally
Time blindness is not carelessness — it is impaired internal estimation of duration. Barkley's externalisation principle is blunt about the fix: move the function out of your head and into the environment. A large visible countdown does the tracking so your working memory doesn't have to. For professionals, this is the difference between arriving at a 2pm meeting having done the prep and arriving having intended to.
Try this: Start every work block with a visible timer running, even for a 10-minute email pass.