Woody - Question about molding (not mildew)

Woody,

Have been looking on at your process of building the Baton Rouge model.  What/how/who/hey do you do that casting of the parts for molds?  What is the blue stuff you use? Where can a guy get directions for making casts?

Just tell me please how do you do that whole thing?

I want to make some molds and work on some casting of a few things that just aren't available on the market, mostly for personal use, but also just want to learn something new.

Thanks much!