Nisten

Hi there. I understand you need to open the ports in order for others to join. However, should I need to do this if I have DMZ enabled on my router?

Sorry for being such a noob, but I looked everywhere without any luck. What is the easiest way for two friends to join up? When I host my own server, it doesn't give me an IP address that I'm able to pass along to my friends. When I search for his name in the search, it doesn't show up. What the heck is the easiest way to do this? I understand we can join ready-made servers, but we'd like to be able to have our own, just with friends. Thanks