The "Yellow Cross" is the first thing to make for the 3rd layer!
You're only looking at the yellow stickers on the yellow face, specifically the edges only.
The colors on the 4 corners do not matter, and neither does the 2nd color of the yellow edges.
Case 1: You have only one yellow sticker at the center
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Case 2: You have three yellow sticker forming L shape
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Case 3:You have three yellow sticker in a straight line"
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