a few questions I need answered

Hi gang!!!
  I am working on a  new suit and need a few answers.

1. I am making a new DTD and I am planning on using a corset. How do I wear while it making the DTD so I don't cut the corset.

2. What is the best type of Dive suit Lycra vs Spandex and what is the difference in comfort. Also how do I determine the size of the suit ???

3. I am making a female suit and I am male so do I add the silicone padding before or after making the DTD ???

This should be all I need for now and looking forward to answers so I can proceed :)