just walk down to the area where you go to places to do missions your team member should start to talk about it. then it will show you how to be alone.
Chat with our AI personalities
You just need to graduate from the guild go to town head back to the guild and on the way chimecho will show you how to change the leader / make only the leader head to a dungeon
Waterfall pond on floors 6 thru 12 the hm Waterfall is needed to enter the dungeon
just enter these codes in the wonder mail ??M1 CJY? 44?P HF?8 7J6R ...M?1
after you beat chapter 10 you go to the main menu and go down to wonder mail then password then type it in
if you mean so that you only have one Pokemon to enter the dungeon with, then you first have to finish the story mode part of the game, and once you've done that, go on a rescue mission and you're partner will tell you how to only take one person into a dungeon. Hope i helped ;)
You can enter it in the Pal Pad.