I forgot one thing.
Remember BITT - Brake off, Igniters In, Tiedowns off / Throttle closed - or some other regular form of check which makes sure that BEFORE you finally commit to pressing the tit, everything is ready to go.
No I didn't, I forgot two things.
Make sure you don't hold the throttle closed hard against the idle stop - you won't be able to press the button and close the throttle if you do.