Start with the overall picture
Before focusing on individual people, look at the entire image.
Notice the general arrangement.
Are they standing at the same distance from the camera?
Are they posed similarly?
Are they wearing the same clothing?
Does one person appear taller, shorter, wider, or positioned differently?
This gives you a baseline for comparison.
2. Compare neighboring people
Instead of comparing No. 1 with all six other people, compare No. 1 with No. 2.
Then No. 2 with No. 3.
Continue across the line.
This can make subtle