RICHARD: You are going to be wonderful, trust me. Now, did anyone ever to tell you to picture the audience in their underwear? … Well, don’t do it. I did it once and I had nightmares for a week. Bulgarians in Speedos.
An old piece of advice for coping with being nervous before speaking in public is to imagine the audience naked or in their underwear – a stock phrase often used in film and TV, such as on The Brady Bunch, when Jan is given this advice, which somehow assists in calming her nerves.
The idea is that the image of everyone being in their underwear will make the audience seem less intimidating, and you feel more confident. As Richard says, it’s quite useless, and a discredited piece of advice that may very well make you feel more uncomfortable.
The Annotated Gilmore Girls 