Ahh, the receiver won't flash the amber light until the transmitter is turned on.
So here's what you do: unplug the heli. set the TX like you want it to bind--all trims neutral, idle up off (normal flight mode), throttle hold off, throttle stick low, rudder neutral, cyclic centered. Turn TX off. Put bind plug into the batt. connector of the rx. Plug in heli power--usually the BEC on the main motor ESC. Hold down the back button on the TX while you turn it on. Now the amber light on the RX should flash for a few seconds. Keep holding the button on the TX until the RX light turns solid. When the RX light turns solid the system is bound. Unplug the heli, turn off the TX, take out the bind plug.
You should be good to go.

I once bound mine to Idle-up by mistake...wow what a mess.

Let us know if this solves it for you.