Hello,
Check these Articles:
How To: Create an unmanaged client install package from the SEPM with custom policies.
http://symantec.com/docs/TECH105498
Exporting client installation packages
http://www.symantec.com/docs/HOWTO55412
About migrating unmanaged clients
http://www.symantec.com/docs/HOWTO26715
Migrating unmanaged clients with exported packages
http://www.symantec.com/docs/HOWTO26713
Managing client installation packages
http://www.symantec.com/docs/HOWTO55410
For SEP 12.1 unmanaged client, licensing is required. If we install unmanaged client Sonar, IRON and other new features do not work. To enable the submission of reputation data from an unmanaged client, you must install a paid license on the client. Use the following procedure to install a license on an unmanaged client.
VIDEO: https://www-secure.symantec.com/connect/videos/sep-121-licensing-unmanaged-client
Article: Licensing an unmanaged client http://www.symantec.com/docs/HOWTO54944
Hope that helps!!