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More information can be found here: https://quizlet.com/blog/dont-have-a-quizlet-account-heres-why-wed-like-you-to-create-one
Quizlet is a very effective resource for quick learning of key terms and language - that's all. That's not to say it is not important but one might argue that the best direct way to really be ready for the listening exam is exam practice questions and papers.
With that being said, the ultimate way to be ready for your listening exam is a combination of lots of things which are all explained here. Use them all, including Quizlet to fully prepare yourself.