After topstitching in a heavy thread parallel to the edge, I started by pencilling using my ruler as a guide.
This happens to be nearly perfect for my torso length.
Then I used the ink pen to trace over. I made the decision to do this over the mannequin but the adjustable areas made the pen move in unintended ways so I’d recommend not doing that and instead following the next step.
I then cut a piece of foamcore to fit inside the shoulders and started to paint the ink.
The ink was soaked overnight in Isopropyl alcohol, about 1/2 cup, and I strained in before transfering to a narrow bottle.
I then put a shallow dish of IA out and a smaller dish of ink out. I used a mop like brush to paint IA over each section before using just the end of a flat synthetic to sweep the ink on in strokes parallel to the marked lines.
I did this on the front then turned the piece with foamcore to work on the back.
I then soaked the sleeves in very thinned ink and left it out to dry.
I used IA to speed the drying time and avoid transfering ink as could happen with just water. However I recommend that method if you have time and space.