> On the other hand, I've known a few people who are able to clock in and clock out, do a competent job, and not get too stressed about stuff. I'm still trying to figure out how they do it.
This is an amazing skill I only learned during a PhD, and only after burning out half way though.
Obviously, step 0 is clear boundaries and reasonable work hours. Clock out at 5 or 6 (or 7 or whatever -- point is, put in your 40 hours and leave).
After that, things get more difficult.
For me, the answer was to work out directly after work (so before the commute home even!) and to listen to an interesting audiobook/podcast during my workout.
That way, when I got home, I would have something on my mind other than work. Fortunately, my personality is such that as long as the audiobook/podcast was interesting, that's what I will focus on/think about the rest of the night.