Greetings!
For two 2930F switches with existing configurations, you will need to choose one of the two to designate as the initial stack Commander; this switch will retain its existing configuration when VSF is enabled. Make sure to back up the configuration from both switches before starting, in case you need to restore them to standalone operation later on or to use as a reference when re-applying the member 2 configuration after building the stack.
Once you've enabled VSF and rebooted the first switch, configure at least one VSF link port and connect it to the second switch.
The second switch will need to be factory reset in order to join the new VSF stack; once this is done, apply the appropriate member-specific configuration from a management console on the Commander.
As far as building the stack remotely — one requirement is that the two switches have to be directly connected to each other using the port(s) you intend to assign as VSF link interfaces, so this would need to be done before the stack can be built. The rest of the process can be done remotely (via SSH, remote terminal server, etc), and once the stack is operational you can manage the entire logical device from a single IP address.