Sewing: How to Grade a Seam
- 1). Sew your seam and press the seam open with an iron.
- 2). Hold your scissors at an angle so that the seam allowance closest to the outside of the garment will be the widest one when you cut down the seam allowance. Trim the seam allowance in half to grade both sides simultaneously for a facing seam.
- 3). Grade a construction seam by trimming one side of the the seam allowance in half and cutting one-quarter off the other side.
- 4). Turn facings in and press them down with the iron.
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