Ummm... Unless I'm misreading this, this will not change your external IP.
It looks like you start out by changing your local IP address to 192.168.0.1. This does nothing but set your local IP address(meaning the one that your computer is referenced by in your local network). Usually your default gateway is 192.168.1.1 or 192.168.0.1 and 192.168.1.254/192.168.0.254 are simply the last assignable host address in those networks using the subnet mask of 255.255.255.0. None of this has any affect on your external IP(what GGG sees)
Then you set your DNS to google's DNS server. A Domain Name Server serves the purpose of translating a human-friendly name(www.google.com, www.pathofexile.com, www.exiled-bot.net etc.) into its assigned IP address(This is what is used to actually route your data). IIRC you only contact a DNS server when you do not have the information stored locally. Go to your command prompt and type 'ping www.google.com', it will reply with something similar to the message 'Reply from 74.125.139.147: bytes=32 time=42ms TTL=41' four times. Along our ping's path a DNS server has translated 'www.google.com' to it's associated IP address of '74.125.139.147'(Bit more complicated but works for this example.) This has NO affect on your external IP.
Your external IP is assigned by your Internet Provider. They are assigned in a static or dynamic way. A static IP will RARELY(Read: pretty much never) change under normal operations. Dynamic IP assignments will expire after a predetermined time and you will be assigned a new one. If you have a static IP address(seems to be most common) the only realistic ways to get a new one are to contact your provider and ask for a new one or spoof your router's MAC address as it's usually used to determine a user's IP address. If it were as simple as simple as your instructions nobody would pay money for a VPN simply to have a separate IP.