Most commercial patterns don't fit perfectly straight from the envelope. Understanding how to grade and adjust a corset pattern for your measurements produces a far better result than simply cutting the closest size.
Grading Between Sizes
If your waist falls in one size and your hip in another, you need to grade between sizes — transitioning from the smaller size at the waist to the larger size at the hip. On a corset pattern, this is done by blending the cutting lines across the hip panels: cut the waist portion at the smaller size, then gradually blend outward to the larger size at the fullest hip measurement. This is a straightforward alteration that significantly improves fit for curvier figures.
Full Bust Adjustment (Overbust)
A full bust adjustment adds circumference at the bust apex without changing the underbust or shoulder measurements. Method: slash the pattern piece from the bust apex toward the side seam; spread the pattern by the amount of additional circumference needed (half the total adjustment, since you're adjusting one side of the front); redraw the cutting lines. The FBA is essential for fitting overbust corsets to large or augmented busts.
Torso Length
Shorten by folding a horizontal tuck across the pattern piece; lengthen by slashing horizontally and spreading. For corsets, length adjustment is typically made at the waist panel (between the waist and hip measurement) rather than at the top or bottom edge, which would affect the curve of the silhouette.
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