When you are working with a haphazard method like this you have to beware of holes that can be created when you join new pieces to the existing piece.
In the first pic (if they load right) is the layout for missing the hole.
In the second one you can see the head of the red pin is in the hole
In the last pic you can see the back side and how the hole looks.
When you lay a swatch across you need to pay attention to where the fabric swatches end. Those can create the holes if you sew a piece across without making sure your swatch is on solid ground! (so to speak)
Avoiding a hole
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Front - red pin head shows the hole
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Back- red pin head shows the hole
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