A paper model is a good first step because the materials are cheap and easy to work with. Modeling clay, etc are good second steps.
For a first timer CAD modeling is a lot of investment, but it's definitely where you want to be. You can buy a desktop 3D printer now for $5k (http://www.desktopfactory.com/our_product/).
For a first timer CAD modeling is a lot of investment, but it's definitely where you want to be. You can buy a desktop 3D printer now for $5k (http://www.desktopfactory.com/our_product/).