Using the Pen Tool for a Perfect Fit
There are several ways to use the pen tool to help achieve a perfect fit. For example:
In the 3D window, use the pen tool to mark drag lines or other fit issues. These can then be viewed in the 2D window on the actual pattern pieces.
In the 3D window, use the pen tool to mark the desired hem or sleeve length. Again, this can be viewed in the 2D window to help make the required adjustments.