you want to use standard wifi when you are usually roaming on your job or home network, just as you have done with earlier handsets.
this should be explained in your manual.
you can also smoke over this wiki on it:
Wi-Fi Direct - Wikipedia, the free encyclopedia
and from the horses mouth:
Wi-Fi Direct allows Android 4.0 (API level 14) or later devices with the appropriate hardware to connect directly to each other via Wi-Fi without an intermediate access point. Using these APIs, you can discover and connect to other devices when each device supports Wi-Fi Direct, then communicate over a speedy connection across distances much longer than a Bluetooth connection. This is useful for applications that share data among users, such as a multiplayer game or a photo sharing application.