Very little is free in this life, especially when onboard a flight. However, follow these simple steps next time you're on a plane and you might land yourself a free drink.

As incredible as it is that we can fly pretty much anywhere in the world in a matter of hours in 2019, it comes at a price. Getting a flight is expensive, and often more expensive than airlines will lead you to think. On top of the initial advertised price, you could be expected to pay extra for a bigger bag, and even if you want to choose where to sit.

Then there are the prices when on board the plane. As with any walk of life where a company knows they have a captive audience, everyday items that normally don't cost too much will set you back a small fortune when in the air. If only we had forked out a lot more money to be sat in first class and get a complimentary drink.

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Well, as it turns out, you don't necessarily need to be sat in first class to get a free drink. Ex-flight attendant Shawn Kathleen revealed to SFGate what would prompt her to give a passenger a free drink, and it sounds as if it's basically a rule of thumb among most flight attendants.

It's not some convoluted code or crazy handshake either. The key is to simply be nice. It might sound simple to some, but Kathleen explained how hard it is to even get a "hello" from most passengers, let alone a "how are you?" Kathleen also explained that a little gift goes a long way and that if a passenger gave her some chocolate, she would definitely return the favor with a free drink.

Try to treat your flight attendants the same way you would treat a waiter at a restaurant, or a pizza delivery person bringing you food. In many ways, flight attendants are doing a lot more for you than those in other professions, so why do they not deserve a tip of some sort? Plus, who knows? Next time you do so, you might get a free drink out of it too.

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