Many many years ago, I started using AutoCAD, then all command line! these days things have changed!! check out the new offering from Autodesk best of all you as a hobbyist can use it for your 3D printing projects FREE! just download and register as a non profit, maker. download from.. http://www.autodesk.com/products/fusion-360/overview
why not try TinkerCAD? online 3D CAD software again for FREE! find it here… https://www.tinkercad.com/
I know! its mad, we live in a technologically amazing time, have fun with it share your files here with other people?? why not??