Virtuemart - Add additional description fields to products

I'm having issue finding a bang on solution开发者_如何学Python for this. I'm pretty sure I've narrowed down to what files need to be modified and somewhat what it is that needs to be added to make this happen. I'm clearly missing something.

According to the VM developers, if you need extra fields for products, you use product types to make that happen. This allows you to add custom fields without hacking any files.

http://virtuemart.net/documentation/User_Manual/Product_Types.html#N20E96