To set your home, you press the "b" button, or you click the feather from your list of actions on the bottom of the screen. When you do this, your character's name and your username appear. At the top of the bar is "Bio" and "Home". As you should have guessed, you click "Home" and click "Set Home". Your home is set exactly where your character is standing. Once you click "Go Home," you go to the exact part you character was in. So if you FINALLY reach the top of Ascension Island, then guess what? You can set your home and be able to go there any time you want. And the color of the group chat is a dark green, unlike the General chat, which is a lighter version of group.
Source: Mah brainzzz.