Whenever you fly, you should dress up. Wear the nicest clothes you have that you can still feel comfortable in. Gentlemen, that means jacket and tie; ladies, a suit or dress. Why? Glad you asked.
A long time ago, a travel agent told me, "Be sure and dress up when you fly." I wasn't opposed to the idea. In fact, the words "clothes horse" had been directed toward me on occasion. I took his advice and from then on, whenever I got on a plane, I always wore at least a jacket and tie, but usually a suit. Turns out, the agent was right.
More times than I can count on fingers I have been pulled aside while the rest of the passengers boarded. And after those commonly clad travelers had disappeared down the jet way, I was escorted to a first class seat. Yes, that's right. The plane was either overbooked or, for one reason or another, there was an empty first class seat. And because I was dressed like I could have been a first class passenger, that's where they put me. This has happened on both domestic and overseas flights and included all of the perks, food, cocktails and entertainment that come to those who actually purchase a first class ticket.
Even if you don't have the good fortune of being bumped up to a butt-friendly, back-friendly, leg-stretching seat up where the beautiful people fly, believe me, you'll have a better flying experience. Flight attendants and even the other passengers are much friendlier than if you had worn your favorite jeans. So, dress for first class and watch what happens. Bon voyage!