My friend and I have been trying for nearly an hour now, we have no idea how to do it. When we exchange IP addresses it sticks on the connecting screen forever. How is a modern game this fucking hard to get multiplayer going.

You run the server, then connect to the ip. I've had no issues doing this with my friend.

Terraria has a weird way of setting up a multiplayer server. The easy way out is ofcourse using hamachi. Download it and find some instructions about setting it up, I personally prefer port forwarding, but tha is a little harder to set up, to port forward u must first creat a static ip and stuff. I would try and use hamachi, its the easiest.

Good question, it's damn near impossible.

One person runs the TerrariaServer console app, the other person conects to it. Make sure whatever port you are using is forwarded.
 
No issues here at all.

its default port is 7777. if you're behind a router you need to have the port forwarded to the machine hosting the game. if you have a firewall it needs to allow that port.

you have the option of host & play from within the regular game, but then the host can't use the disconnect / reconnect trick to quickly get back to the spawn point. the other option is to download the dedicated server from terraria.org — i haven’t actually run that yet but a friend of mine did and i connected to it fine.