This is something I am constantly working on... Taking responsibility for what you can influence and not pushing the blame or anger onto someone or something else.

These days shifting blame or worrying about things that are out of your control seems to be a constant. One of the small ways I try and take back some responsibility is in traffic. Traffic is always bad in my area especially in the mornings when I have kids to get dropped off and my own school to get to, but by realizing that getting angry and shaking my fist at someone who cuts me off doesn't do any good it has made my morning commutes a bit less stressful. The crucial step is accepting that when it happens I still DO get angry and my heart rate picks up a little and acknowledging that fact, but not letting it boil over into me yelling at my windshield.
This is just a small thing, but it is slowly spilling into other parts of my life and while I still experience stress and disappointment and anger identifying those things and seeking to do what I can to change them instead of waiting for someone else to do something has been very beneficial.

I think the root of it is that its so much easier to shift the blame instead of doing the mental work it takes to accept fault or responsibility. It takes work and mental strength to focus on your actions and role versus the easy way of simply placing the impetus on someone else. Unfortunately, most people don't want to do the work.