Enter Network Settings.

Choose the Ad Hoc Mode.

Select the channel in use for the PSP™

Press the "O" button to save settings you've made.

Start the game "Monster Hunter Portable".

Go to the place where can enter the lobby. Choose X to be online and enter the lobby. (If choose "□" to be offline, you can play the game without other players.)

If selecting online, it will automatically connecting the gaming room.