If you just need 2D drafting, stop using AutoCAD 2010. is a near-perfect clone of AutoCAD’s interface, reads/writes .DWG files natively, and offers an official portable version via their "DraftSight Portable" (available for enterprise customers).
If you are looking to manage your license or use the software on different devices, here are the official tools and considerations: autodesk autocad 2010 portable updated portable