I am not sure about headless mode, I have a feeling that it really doesn't work. If I hold left upper button for awhile the remote controller makes some beeps, but can you see anywhere on display to check if its really enabled?
There is no indication on the Controller Display as to what Mode the Quad is in.
To activate "Headless Mode" make sure you are executing the following steps, in the order listed....
Push the Controller ON/OFF power switch up to turn it on, and then turn on the power switch on the bottom of the aircraft.
Assuming you are in the "Smya flying Mode 1" state, push the left throttle lever Up to the highest position, hold it there for several seconds and then pull it back to the lowest position. The transmitter will sound a long Beep to show that the quadcopter has established a radio link and a "forward" direction, and has entered into the pre-fly state.
After executing a "Forward" definition, the aircraft defaults to non-headless mode, and the all indicator lights on the aircraft will lite in a steady bright state.
NOTE: The "Forward" direction of the Quad is the way the camera is "looking." The battery access door is at the "Back" of the Quad. For ease of quickly determining the orientation, I suggest drawing a forward pointing arrow on the top surface and then making sure that arrow is pointing away from you when you set the Quad down in preparation for flight.
To set the "Headless" mode, press down the headless function switch on the top left of the controller for > 2 seconds, the remote control will give out a burst of short beeps to confirm it has entered into headless state, and the aircraft LEDs will flash for ~4 seconds. Pressing again for >2 seconds will exit headless mode, and the controller will emit one long beep for confirmation and the aircraft LEDs will be steadily lit.
As you initially lift off to fly, verify the Quad moves away from you when you press the Left flight controller stick Up (away from you). Doing this right away assures you are flying in the manner you wish, before the Quad gets away from you.