It's supposed to align with the edge to create a continuous line. Sometimes it requires playing with the front and back edges. Usually, I start by aligning the center notch. More than once I've confused the front and back sides. This may sound crazy, but because the shoulder blade is angular, I always want to put the fuller side of the pad facing the back instead of the narrower side. It's especially bad if the shoulder pad has a front and back that are similar in shape -- but maybe that's a low-quality pad.
If it's not possible to make it conform, you can take your pattern, place it on top of the shoulder pad, trace the outline, trim the pad, remove any excess wadding and stitch it closed by machine or hand. You can also make your own pads. Trace the shape, add seam allowances, cut out two in muslin, then take the wadding from the commercial pad or another source, add it, and sew it. There are videos online that demonstrate this.
It's also possible to make custom sleeve heads with strips of muslin on the bias.
It's supposed to align with the edge to create a continuous line. Sometimes it requires playing with the front and back edges. Usually, I start by aligning the center notch. More than once I've confused the front and back sides. This may sound crazy, but because the shoulder blade is angular, I always want to put the fuller side of the pad facing the back instead of the narrower side. It's especially bad if the shoulder pad has a front and back that are similar in shape -- but maybe that's a low-quality pad.
If it's not possible to make it conform, you can take your pattern, place it on top of the shoulder pad, trace the outline, trim the pad, remove any excess wadding and stitch it closed by machine or hand. You can also make your own pads. Trace the shape, add seam allowances, cut out two in muslin, then take the wadding from the commercial pad or another source, add it, and sew it. There are videos online that demonstrate this.
It's also possible to make custom sleeve heads with strips of muslin on the bias.