Hi, I'm a bit new to this game, and I wanted to create a server for just my friend and I. Well, I went to "Create Game" and edited the settings to my liking, and then I started the server. Everything was ok, except for that fact that my friend couldn't find the server in the server list. I don't think I made a LAN server, but I don't know how to check. Then my friend made a server, doing the same things I did, and I could see his on the list. So everything was ok, but then the next day when we wanted to play again, I couldn't see his server this time.

So my problem is, how can you make sure your listen server will be on the list, and is not a LAN server.

Thanks in advance.

Try >bevore< you start the server in the console: sv_lan 0 .
Go to http://www.whatismyip.com/ and give you friend you ip with the port :21015 e.g.: 123.456.789.012:21015 , your friend should connect now.
Or try the dedicated server from the files page. (It also need some time to get you server shown up in the list)