Usually candidates either get a map or diagram type of questions in section two of the IELTS listening test but luckily since it will have one speaker who guides through the diagram, they can easily follow and find the answers. Initially, the candidates should make use of the time gap given before the start of listening transcript, during which they should check the answers which are needed in the diagrams and check the parts to which they are about to be labelled. Candidates must also read the parts in the question, for which it has been already labelled; they should be well versed with it so that during the audio, they can easily mark the location. By following these two steps, they can easily understand the diagram.
The image may be of a device or a flow diagram, in which few parts will be labelled for guidance and remaining parts will be left blank. Candidates should practice these types of sessions by hearing more documentaries regarding the labelling of any equipment or any process such as conversion of solar energy. Finally, we should also check for any spelling errors and since small font might hinder in representing the correct spelling to the examiner, capital font can be writing throughout the listening. At prestige institute, IELTS coaching classes are conducted on regular basis for the above strategies, so that the candidate can score band 9 in these types of questions. Candidates can also practice with the hundreds of mock tests which the institute will provide during IELTS coaching classes.
References
https://ieltsonlinetests.com/listening-tips/how-do-diagram-type-questio…
https://ieltsforfree.com/labelling-a-diagram-in-the-listening-test/