Yugioh

[Krillin]

Usually, you click Duel off the initial load-up, and it will bring up a Deck Editor. Then, when you click "Use this Deck" (after creating/loading your deck), you will be brought to the game field. From here, either send your IP to the person you wish to duel with (if you're hosting the game), after which they'll put it in the Connect screen, or you need to get their IP (if they're hosting the game), at which point you'll need to put it in the Connect screen. Whoever isn't Connecting has to be Listening BEFORE the person tries to Connect, I believe.

From there, you should be connected, as long as neither of you have firewalls or crap gumming it up.