You get a set of photographs with a task printed above them. You talk on your own for about a minute, comparing the photos and answering the task. Then your partner has a turn, and you answer a short question about their photos.
The key word is compare. Describing each photo in turn misses the point: the examiner wants to hear how the photos are alike and different, and what you think about the question.
Spend very little time saying what's in each photo. Go straight to the comparison: 'Both photos show people studying, but in the first she's on her own, while in the second...'. Words like whereas, while and both do the work.
The task above the photos always asks you something: why people are doing this, how they might feel, what the advantages are. Many candidates forget it. Give a good part of your minute to answering it directly.
You can't know what's really happening, so speculate: they might be, she must be, it looks as if. Use a range of these instead of repeating maybe in every sentence.
A simple plan works well: a quick opening on what the photos share, the main comparison, your answer to the question, and a short final thought: 'So, on balance, I think the people in the second photo are having more fun.'
While your partner speaks, listen. Afterwards you answer a short question about their photos for about 30 seconds: give a clear opinion and a reason. It's short, so don't start a new comparison.