Kamailio

I read blog on the internet about Kamailio & I have installed the Kamailio on my Ubuntu virtual machine. On the request_route section, I've configured the below:

request_route { xlog("I got a message"); sl_reply("501", "Not Implemented"); }

Now What I don't know is, How do you set up and register a test SIP endpoint and point it at the Kamailio instance? I am brand new to all of this. thanks.