In Part 3 of the IELTS Speaking test, you will be asked a few discussion-type questions. To get Band 7 or higher, you need to use a good range of vocabulary, linking words and phrases (I would say, as I said, etc.), a variety of simple and more complex grammar structures and clear pronunciation. To get Band 7, you can make a few more mistakes compared with higher bands. Check out this Band 7 sample answer from the IELTS official YouTube channel.
This will give you a good idea of what you need to do to achieve your target band.

You can find many more tips like this in the IELTS Speaking Masterclass course, an essential programme of training materials for IELTS Speaking including videos and downloadble pdfs.
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