How do I trigger a Sigma EF 610 flash remotely from a Sony A290 camera?

Busch is right, but the manual - at least for my 610 Super - is for sh*t.   Before you put the flash on the camera, you need to turn on the gun, select TTL-FP Remote and then press the Sel button until the display stops blinking.  If you miss out any of the steps in the manual, go straight to Jail.  Do not pass Go.  Do not collect $200.  NOT necessary to turn off the gun at this point.
Now you can attach the camera (in WL mode) to the camera.  Half pressing the shutter button will bind the channel you selected to the camera.
Detach the gun - still turned on - and place it where you want.  Pop up the inbuilt flash on your camera.  Take the shot.
I have had my 610 for about 10 days.  I get it right about 10% of the time.
Happy new year!

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