Flight attendants say you should wear *this* type of outfit to get a first class upgrade

Next time you're heading on a long-haul flight, you might want to remember these flight attendant secrets.

From the secret button on planes to the one drink that crew members repeatedly advise against ordering, befriending a flight attendant is not without its benefits. Learning the tricks of the trade might even earn you a first class upgrade, without the extra charge that frequents the promotion.

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Sometimes, getting an upgrade isn’t about those frequent flier miles or knowing the right people. Sometimes, it’s about something as simple as what’s in your closet.

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It’s far better to look "smart but understated,” said one flight attendant to Travel and Leisure. "You should look like you travel often ... It helps; someone who is potentially due to get an upgrade can be knocked back if they aren't dressed suitably.”

So, is it worth forgoing our airport sweatpants for a nice pair of pants, in exchange for some first class service? 100 percent!

Watch the video above to learn some more insider airport tricks!

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