I am a very introverted person. I am somewhat awkward in social situations. I think when you are more inward-directed, it's easy to focus too much on yourself, whether it be overanalyzing, nitpicking, or over-thinking situations or characteristics of yourself.
I am also not the most patient or tolerant person. I am easily irritated by others and don't always take my own advice, which is "seek to understand before being understood". To combat this, I have made a concerted effort to just be nice, even to people I don't like or who I think are rude.
It's amazing how much better I feel.
Having a pleasant interaction as opposed to a tense one. Not worrying about being right. A little gesture of kindness.
I am certainly not advocating being a doormat but, for me, trying a little harder to be more positive, friendly, and kind has helped shift my focus outward and in a more positive direction.