Spent a few minutes today recalling some of the stupid things I've done in my life. Found myself acutely embarrassed, and felt a lot more forgiving of others doing equally stupid things. It's a salutary exercise, perhaps one that should be repeated at least once a day. Helps you keep a sense of proportion and ensures you'll never believe your own publicity. I recommend it.
(And, no, I'm not going to confess to the exact nature of any of the stupidities. It's just way too embarrassing to even think of doing so.)