Well, I bought some black and red cotton canvas and here we go.
I cut out the pattern. Once from each colour.
I added gores to the shoulder slits and sewed the center-front and center-back seams.
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I could press the seam allowances but I had to trim them at the curves.
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I sewed the two hoods together at the lower edge. I sewed right side to right side.
I also sewed the seam allowances at the tip of the liripipe together. For easy changing of the colour of the hood:-)
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I folded a cm at the face edges in and ironed.
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I basted the edges and sewed together at two milimeters from the edge. I ironed the lower hem and sewed this way as well.
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That's all:-)