Today I went with an experienced freefly coach to try to work on back flying and sit. It was my 79th jump. Shortly after a bad attempt at a sit fly exit I got to my back and got into a flat spin. I went back to basics from AFF and tried arching hard to get back to my belly and stable with no results. I tried bringing my arm in to flip me back to my belly, but that also didn't work. I checked my altimeter, but even though I could see the outline of the altimeter I couldn't read the numbers. I am not sure if this was from moving so fast, chaos in my brain or just general disorientation. I kept working on body position trying to find something that would work. At around 4500 something finally worked and I got stable enough to pull. The problem is I don't know exactly what I did to get out of the spin. I have since watched the video of the jump, talked to other jumpers and read some on the forum. I have read that some people suggest trying to get into a track to slow the spin and others suggest getting into a ball to stop the spin and then arching to get stable again. I was shocked at how disorienting the spin was and how hard it was to get stable again. I am just looking for any thoughts/feedback on the best and quickest way to get out of a flat spin when arching and bringing an arm in isn't working. I have to say I am a little hesitant to get back in the air out of fear that if I got myself into that position again that I couldn’t get out of it. (p.s. yes, it was probably too soon to freefly and doing a sit exit without being steady on my back was a bad idea. I am putting all that on hold as a lesson learned but still want to learn how to get out of a spin in case it happens in another situation)