If you believe sitting a certain way helps you WILD, then that position will help you WILD. Positions while WILDing are just habit combined with placebo, as long as you are comfortable and can feel safe and secure in your position , then that position is right for you.

I personally WILD on my side because that's how I sleep. I've tried WILDing using the positions ThreeCat describes and, due to habit, I've only been successful using the sleeping lion posture. Although I can meditate in the other two positions, I don't feel comfortable enough to fall asleep.