Perhaps the hardest thing about the IELTS listening test is that you only hear the recordings once. If you miss something, there's no second chance.
However, when practising or when listening to anything in English at home, I recommend that you listen to the same thing several times. Every time you listen again, you'll probably hear something new, and your listening skills will improve more quickly than they would if you only listened to everything once.
Here's a good listening exercise:
- Listen to the same short recording several times.
- But each time you listen, focus on something different.
For example, first focus on the meaning or the overall message, then listen for the answers (if you're using an IELTS test), then listen to verb tenses, then listen to the speaker's pronunciation, then listen to the little words like articles and prepositions etc. etc.
Your "ear" will improve more quickly through repetition and through the kind of deep listening that the exercise above encourages. Try it yourself!