This tutorial details how to shorten a pattern without making changes to the shape or width of a hemline. If you would like to simply "cut-off" a pattern (for example would like to make a dress pattern into a shirt pattern), this tutorial may be more appropriate.
I have used a standard set-in sleeve for this example, but this technique can be used to shorten any pattern.
Take your sleeve block and focus on the ELBOW LINE – this will become the “Lengthen and shorten line.”
Cut along ‘lengthen and shorten line” – separating pattern into two pieces (upper sleeve and lower sleeve).
Decide how much length you would like to remove from the pattern and mark a point this far above the cut line on the upper sleeve. Draw a perpendicular line (perpendicular to grain) through the pattern from this point.
Move lower sleeve up so that the top edge of the pattern is laying on top of the perpendicular line. Fasten in place with masking tape.
Redraw the seams of your sleeve by drawing a straight line from the bicep line down to the wrist line.
Trace your pattern onto a separate piece of pattern paper and add seam allowance.