What should speakers wear?  I’ve posted on this fiendishly difficult question in the past and it seemed time to do so again, since neuroscience has weighed in on the subject recently.  But first, some of the same basic issues remain, with the fresh twists that the ever-changing fashion world always provides.

1.The trend continues toward more casual dress. If it’s OK to go to the mall in your pajamas, what fashion taboos are left?  The business world similarly has just about given up on the tie except in certain strata and industries.  Jeans used to be a no-no at conferences, but have mostly completed their world invasion.

In this increasingly low-fashion context, speakers need to be very careful not to overdress.  You don’t want to send the signal to your audience that they’re headed for an old-fashioned, stuffy, overly formal hour.  (Of course, with speaking times shrinking at the same time, you’re lucky to get an hour.)  And yet. . . .

2.You still need to dress better than the audience. Partly it’s to suggest that you take the occasion seriously, and partly it’s to create a visual sense of your expertise as the speaker.  So men, don’t show up in a t-shirt and shorts.  That’s probably the one taboo still left.  And yet. . . .

3.You need to dress to signal your tribe more than ever. So what if you’re a skateboarder-thought-leader who talks about how everything you need to know (about risk?) you learned while skateboarding?  It might be shorts and a t-shirt for you.  Further up the intellectual food-chain, the business world messily subdivides into various tribes and you need to signal yours.  Are you a designer?  Then wear something very, very funky.  Are you a creative? Ditto, with perhaps a sport coat to show that you’re able to talk to the business types.  Are you an entrepreneur?  Start from the ground up, and spend most of your wardrobe time selecting your sneakers – they seem to be key.  And yet. . . .

4.You also need to figure out your personal brand and dress for that. As a former academic, I’m always going to be in some personal variation of the jacket-no-tie on top, with either jeans or trousers beneath.  I used to firmly believe that I looked great in a t-shirt underneath the jacket, until I read a piece by a fashion expert (who seemed way more knowledgeable than me) who said, “No. Just no.”  So I put the t-shirts away and went back to button shirts.  The goal is to find personal touches that signal your brand to the audience, in a way that’s smart, elegant, and not too trendy, unless to be on trend is your topic.  And yet. . . .

5.No matter what, don’t wear red. This holds true especially for women speakers. Recent studies have found that if a woman wears a red dress the men believe that she’s signaling her sexual availability.  And the women in the audience are more likely to criticize her, in order to take her down a peg and make her less of a threat.

Does this red danger signal apply to scarves, ties, blouses and the like – a dash of red to liven up an otherwise drab outfit?  Science can’t tell us yet.  But clearly, these are murky waters and so I think it’s best to avoid red altogether.  While the studies didn’t find a similar effect for male fashionistas, given the emotional content of the color I would steer clear of it.

How do you navigate these complicated social mores, signals, and changing values?