Advancement in this pose

I remember being stuck in this very same spot for a long time. What finally worked for me was, not only focusing on shifting all my weight forward to my shoulders, but also putting my chin on the floor and stretching my throat forward to the floor. This of course assumes you have no neck issues and can safely do that with your neck. I actually lift my chin up a little off floor to stretch my neck and make sure my weight is focused on my shoulders. Once I have that established then I bring my chin back down to the floor. It took a little bit but once I started focusing on that I was able to pretty quickly get my legs higher up and hips up. Hope this helps!

Hi Akshaya,

I suggest thinking about more "forward" than "up" as Martha said.  Right at the beginning of this posture, there is a shifting forward that needs to happen in order to access the muscles of the upper back, which is what you are trying to contract in this posture. 
Think about using your hands a lot to grab the floor and contracting your triceps to create the shift forward and up. It will probably feel like way more triceps than you usually use!
It is ok if your shoulders do not touch the floor. Some people's never do even when they have a deep posture. This is sometimes related to one's anatomy. 
Some people can feel upper back contraction and some cannot. If you can't feel it yet, keep connecting your mind to that area of your body each time you try the posture. The more you ut you mind there, the more the area will start to respond!