Lizard if you go to the helmet section you can see how I am molding my helmet. When I finish the mold and start the casting, that will be included in my thread as well. Mine is made of hydrocal (plaster) and you would probably need to reinforce yours from the inside before you attempted to make a mold since it would deform. The techniques I use could be modified to suit your needs, but I think you are going to find the process fairly involved. Another suggestion is to look into some of the training videos available. I taught myself mostly from the Gnomom videos with John Brown, Sculpting and casting. Most of the gnomon videos deal with computer graphics training, their analog training stuff is wonderful. Experiment with materials and techniques, but do it safely. Try to find someone near your area who might have more experience who is willing to work with you and help you if possible. Best of luck.
-x