turn on nfc and make sure the nfc of another persons phone has nfc too and open it. if you want to transfer picture or files just stick both phones to one another facing back bo back with its NFC sticker and traaaa!! files/pics transferred!
And regarding WiFi direct you need an app that supports it. Some phones are shipped with OfficeSuite which enables this option when you for example have a picture open in the gallery and press the share-button.
