That vid is kinda funny, it explains it well, but you don't even see him do it. Not that I'm that great at it, but I'm guessing he can't really hold it. lol
Ok, yeah, I'm pretty sure it's called a 'reverse airbaby', so if you look for that, you might find more pics, info, etc.. But I think it's more about flexibility..
I start out kinda crouched down, on my knees, and put my right arm next to my right foot(you can switch lefts and right and see what is easier for you). Then turn your foot sideways and place it on your arm (you can use your free hand to halp with this 'cause it's kinda tricky). Once you're there, you can straighten your other leg and start leaning/jumping backwards balancing only on your hand.
Depending on how flexible you are, place your foot higher on your arm. I can only get it a little above the wrist, but I've seen people get on their elbows, and it looks incredible..
Hope this makes sense, let me know if you have a question or are confused.