A good way to work on your listening is by transcribing what you hear. Transcribing means writing down the full text of a recording. You might find it difficult and laborious, but this is the kind of hard work that pays off in the end.
Try transcribing one of the recordings on this website, an online video, or a section of a real test in one of the Cambridge books. Imagine how quickly your listening would improve if you did a short transcription every day!