Starting a DSC on a remote machine is almost just as simple. Assuming you've already set up Powershell remoting (or enabled WSMAN).
$remoteComputer = "myserver.somedomain.com"
$cred = (Get-Credential)
Start-DSCConfiguration -ServerName $remoteComputer -Credential $cred -Verbose
Nb: Assuming you have compiled a configuration for your node on your localmachine (and that the file myserver.somedomain.com.mof is present prior to starting the configuration)