I LOVE this pose, but have not yet mastered it. This is what my peacock looked like 7 months ago.
There are so many variations and ways I've seen people teach this pose. The way I first learned it to start sitting between heels, with knees as wide as possible. Bring hands together about 5-6 inches in front of you, fingers facing forward, bring elbows together and engage abs. Come forward bringing belly on top of the elbows, knees bent at first and toes touching. Bringing the chin forward. Eventually trying to lift the legs up. Different variations to this are...bringing the elbows into the hip bones to balance there. Or having the hands, fingers facing towards you. I never do it with fingers facing towards you but many people do it like this. Also, annoying...guys can sometimes do this pose real easily bc of their tendency to have better upper body strength. Lately, I have been trying to balance more on the hip-bones and since I have been practicing albatross more, I seem to find the balance there.
A great tip for Mayurasana that was taught to me by one of my instructors, was "Peacock Push-ups". Which is to sit with knees wide. Take a few deep breathes, then come forward and not necessarily try to hold the pose, but just come forward and lift the legs as much as you can, come down, sit back down in the same position and repeat. Try 5 at first and then leave the pose alone until next time.
Cool things about this pose that make me love it: Symbolically it represents having lightness with your past. Which is something we all need to learn. Peacocks also have the unique ability to digest poison. As the peacock pose is said to strengthen your digestive system. I've experienced on a few occasions when I've had an instructor hold my legs up as I hold the pose and I feel the bubblies in my tummy -definitely working my digestive system. The pose also asks us to deal with the challenges of the pose itself -To digest the perceived difficulty of the pose as well as the doubt of oneself or poison in order to achieve it. So as I have said, its not so much about achieving what we believe is to be the "complete pose" as much as it is about dealing with the self-doubt and realizing that it is as practice and a journey. So to swallow the doubt and the perceived difficulty, we are ultimately achieving lightness. Keep working on it!