This is a short list of things to do in order to create a joinable server for source games.
Please note that "developer console" must be enabled for this to work.
Also note that some port forwarding is required for this to work.
Please visit
www.portforward.com... for information on how to forward your ports. The port you want to forward for is "steam server"
Visit
www.whatismyip.com... to get your external ip (copy this to your clipboard)
Once the port forwarding has been done, commence the following.