This video will give a method that involves working with a partner to prepare for Pincha Mayurasana (forearm balance).
Please be careful when doing this adjustment. The person who is doing the preparation for Pincha Mayurasana must NOT go up or towards the partner's shins until the adjuster has given clear directions that they are ready for the person to move. You do not want to push their knees backward.Never jump up without a teacher instructing you on correct method.
Working this way with a partner, gives a strong opening of shoulder area and an understanding of where the shoulders need to be for this asana.Always go carefully not abruptly with the adjustment.
The variation with the folded blanket under the forearm give more length to the upper arm allowing for more opportunity to open shoulders .
When you work with turning the hands to face the brick, it makes it a little easier to access the external rotation of upper arm but can be more difficult to ground the forearm down which is what helps to lift the shoulders.
Please check out earlier videos in this series at:
Pincha Mayurasana Preparation: Shoulder Opening with a Chair
Pincha Mayurasana Preparation: Shoulder Strengthening