Use the lens with the longest focal length. A long focal length will compress the space and avoid deformation. Use the distortion correction function in Photoshop to check the barrel distortion that you didn't notice.
Don't shoot from a low angle
You can shoot from a height, but don't forget that this is an abused skill. So don't just have this photo.
You can find a thinner person to block a part of the fat person's body.
You can choose not to take a full-length portrait of them, but try various head and shoulder portraits. But don't let the other person think that you are deliberately not afraid of their whole portrait. Remember that your job is just to take pictures. Don't think it's good for her not to pat her body.
When taking photos of many people, try "squeezing" to make people get closer? Although many photos have been processed now to make them more effective, it is no problem to handle them properly, and more depends on the photographer's skills. Fat, you can also shoot a different taste.
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