I teach at the Museum of the city of New York and I recently made a mistake, and admitted it.....someone immediately said to me "I could never do that!" and we started talking and I got to thinking how I used to have a hard time admitting when I made a mistake, consequently, I had a hard time forgiving others when they made mistakes.....I realized, the bar was just too high for me and everyone else.
Now that I got a little easier on myself and can admit I make a mistake, without beating myself up.....I'm a lot easier on the people around me too....try it!