I'm a former flight attendant. Here are 12 ways passengers ruin their experience on long-haul flights.

I used to work as an international flight attendant and have seen many travelers repeat the same mistakes.

Tiffany Hawk

• As a former flight attendant, I've found ways to make traveling less stressful and more enjoyable.
• Some people drink too much alcohol, which can lead to dehydration and poor behavior.
• Others forget to dress in layers and spend the entire flight feeling too hot or too cold.

As a travel writer who used to work as an international flight attendant...