Next time you think, "I can squeeze this one last task
in before I go," just don't. Recognize it as an example
of false efficiency. Cramming the task in when you
don't truly have time will cause you to: do it badly, be
late for your next appointment, & stress about both.
Leave the task undone for now & enjoy being on time.
Don't: Load Up Your List
Ask, "if this task were the only thing I accomplished today, would I be satisfied?" Find a "yes," put your head down, & do it. Avoid the temptation to reflect on more to-dos. I first read this in Timothy Ferriss' The 4-Hour Work Week -- full of great productivity tips even if you like your 40-hour work week just fine.
Don't: Keep Goofs
Reader Tip: "If you have a piece of 'Goof!' clothing (something you wish you hadn't bought & don't wear), get rid of it. Those things me feel guilty every time I open the closet. When it's gone, no more reminder & guilt." In the words of Peter Walsh, Goof! clothing "exists only to mock you." Donate that sucker!