I normally sleep on my stomach or side, but never on my back. I read somewhere that you had to do WILD on your back, so when I attempt WILD, I do it on my back. Unfortunately, all my WILD attempts have been unsuccessful, not to mention uncomfortable, because of my sleeping position. Is it OK to do WILD on your side or stomach because I believe that would make things a lot easier.
NO! 
its not important, do wild in the position you like most, one where you can fall asleep, it’s say that sleep paralysis is easier when layin on your back, but its not really that important, if you can’t sleep on your back then don’t expect to do it on wild, to WILD you actually have to fall asleep 
Never succeeded in a WILD… Never even had a LD 
But anyways, I’ve read, as jaggs is saying, you can lie in the position you like. Also read that people lie on their back for like 20 minutes until they get these “roll over signals” and then they roll into their normal sleeping position.
All my successful WILDs (two) have occurred while I was in a seated position, so the answer is definitely no.
On a more serious note, like those before me have said before me, you can WILD in any position you want to. I personally used to never sleep on my back, but now do so mainly to WILD. I find it easier to keep my breathing steady and my mind active when lying on my back then when I lay in my usual position on my stomach.
For some reason though, I’ll fall asleep on my back and wakey wakey on my stomach, so clearly I must roll in the night. 
Wish you luck on your WILDing!
That’s false. You can do it in any comfortable position. The thing most people here on forum need to realise is that they have to [color=red]adapt the techniques to themselves[/color] rather than [color=red]adapt themselves to the techniques[/color].
I also have sleeping problems on my back, but when I do fall asleep on my back instead of my stomach, my dreams are much more lucid and vivid 
. Not sure for how many people it actually matters.
No, you don’t need to lay on your back, but for most people it does increase the chance in succeeding. I also have more lucide dreams when I lay on my back, I’m not sure why but I think it has something to do with sleeping less deep.
No, you do not have to be on your back to WILD. I have had two WILDs so far: one on my back, the other on my side laying down. The position should just be a comfortable one. And I’ll give you a tip that I hope will help: the second WILD I had was much more vivid because I was listening to music, music that gave me a sleepy soothing feeling (the album “the city sleeps in flames” by scary kids scaring kids). I wasnt ven tired at first when i layed down. So whatever sounds that put you in a good mood should help.
The only times I ever got SP I was on my back. I also find it uncomfortable so it helps to be in that position when I want to try something without falling asleep immediately.
I think I read somewhere that SP is more likely to come when someone is on their back but I can’t remember anything else, let alone where I read it.