Download OpenVPN client from http://tunnelblick.net:
Open disk image from Downloads folder and double-click the Tunnelblick.app icon:
Follow an installation instruction.
Run Tunnelblick.app from Applications folder:
Add SafeDNS config file to Configurations menu and click Connect:
You can see the connecting process:
When the connection is established the application will have status "Connected" and you will be able to see it in log: