Well, for this purpose you can listen to the English radio, watch good English movies. Talk to someone who is a good speaker of English language (You will get to know more about the pronunciation). Get some audios on how to improve pronunciation in English language.
Learn more about how a particular word in English is pronounced in two different ways. Because, sometimes a particular word in English language is pronounced in two or three different ways. (a word in English is sometimes pronounced differently in US English, UK English, and Australian English etc).
A piece of advice for IELTS test takers:
Now, let me give you a brief picture of what you can, as a test taker of IELTS, do in order to get the best results in your test. Here, I know, it is not necessary for me tell the readers that this test will assess all of the four major skills related to the language. The skills such writing skills, reading skills, speaking skills and listening skills are assessed by the examiners.
Why skills are assessed?
The purpose is very simple. In order to speak English language you need to be good speaker, a good listener. And in order to send across your thoughts in English language through means such as papers etc you need to be a good writer. If you are not a good knower of the English then naturally you will have no chance to impress people round you. That is the reason why all the skills are assess in this test.
In order to be able to either study or work in Australia or any other English speaking country it is necessary that you speak in the manner the natives of those countries do. Otherwise you will be labeled as a non-local.
IELTS Listening Skills 