Your own barometer is all you have to go by, and often what makes a good director is knowing when not to say something. On occasions you can find yourself on a film set where the person who is wearing the director's hat is only trying to justify his position. ↗
When you're walking down the street, or you're at a restaurant, someone catches your eye because they have their own look. It goes way beyond what they're wearing - into their mannerisms, the way they smile, or just the way they hold themselves. ↗
Obviously if you are an accountant, a criminal lawyer, a president, or a senator, or if you work in a funeral parlor, you have to wear a tie, but more and more people are wearing very casual clothes. ↗
Sometimes I'm so tired, I look down at what I'm wearing, and if it's comfortable enough to sleep in, I don't even make it into my pajamas. I'm looking down, and I'm like, 'T-shirt and stretchy pants? Yup, that's fine. It's pajama-y, good night.' ↗