Have whatever you want to beam on your screen, touch phone back to back with phone you want to beam it to, after hearing tone your screen will say "touch to beam"
I know how it works I used it all the time with my EVO LTE. But I tried to beam from my EVO to the One and it didn't do anything. Then I tried it between my One and my wife's S3 and didn't work either. On my EVO in the settings there is a spot to turn on the NFC and also Beam. But one the One there is only NFC??
Remember the antenna for nfc is around the camera module. The other device needs to be centered there. Just sent pics back and forth from my X+ and One