Umanaged to managed and upgrade to SEP 12

Hi,

SEP version 11.0.600

Currently all SEP clients are unmanaged and planning to upgrade to SEP 12.

We are planning to change all the clients from umanaged to managed and also upgrade to SEP 12.  We already have SEPM 11.0.6 installed. Some users are remote and use VPN.

What are the best possible options I have to accomplish the above tasks ? I want to carry out this upgrade smoothly and without interruption the users.

Appricate your help.

Thanks,

Lama