Do the exact same steps for fabric #3.
Now take your fabric for #4, and lay it right sides together over #1 and #3, with the straight edges lined up where they overlap pattern #4 . I wrote the number 4 on the paper so you could see where the pattern and fabric line up
Turn the paper over and sew on the line between #1-3 & 4.
When you are done, fold fabric #4 back, and finger press.
Trimming the final time
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Fabric #4 on Fabric #1 &3
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Sewing the line between #1/3 & #4
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Fabric #4 folded back and finger pressed
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All pieces sewn in place
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