In the United States, the Federal Aviation Administration requires flight attendants on aircraft with 20 or more seats and used by an air carrier for transportation to hold a Certificate of Demonstrated Proficiency. This is not considered to be the equivalent of an airman certificate (license), although it is issued on the same card stock. It shows that a level of required training has been met.

How to pass:
You will have to commit a lot of information to memory, such as Federal Aviation Regulations (FAR) and potentially hundreds of airport codes. You should get in the habit of creating quizzes for yourself in order to test your comprehension and retention of the material you are learning. You may find it helpful to do this with a fellow trainee.
Flashcards are a great way to memorize lots of information and are especially useful when studying without a partner. Create flashcards for terms and their definitions, airport codes, or any other short bits of information you need to know.
Make a note of the topics or definitions you have trouble remembering and set aside extra time to focus on these. This is a great benefit of quizzing yourself: you will identify your areas of weakness before being officially tested on them!


Disclaimer:
This application is just an excellent tool for self-study and exam preparation. It's not affiliated with or endorsed by any testing organization, certificate, test name or trademark.