Configuring Server 2008's Terminal Services Gateway for use over the internet?

Ok, I have recently built a server running Windows Server 2008 Enterprise (It's a legit copy, got it from Dreamspark) and I would like to connect to it via the internet. I already have Terminal Services installed and can connect to it from any other computer hooked up to the same router. I would now like to be able to connect to it via the internet, I have set up TS Gateway and configured it with a self-trusted SSL certificate, now I would like to connect to it, but it just won't work. I check the IP address of my server on whatismyip.com and tried to connect, it doesn't work. What steps should I take now in order to be able to connect to my server via the internet? I will post additional info if requested..