HOW TO - Large scale Mold Making

This is the first part of what should be a great howto series on large scale Mold Making.
We're making an HPV! That's human powered vehicle ;) We are required to have at least 1/3 of our frontal area covered by a fairing (a fairing is just an aerodynamic shell -- like your car's outer skin). We're going for a fully enclosed (aka "sealed") fairing.
To tackle this manufacturing problem, we will be making a "female" negative mold. Similar to how casts of fish are made. To make this mold, we first need to make a positive "male" plug.