After a great workshop with John Aplin on Saturday at iYoga I have changed my approach to Sirsasana.
John suggested trying using the wall facing the opposite way. With my feet against the wall I measure the distance to my hips and place a marker down. I then put the crown of my head on the marker and came into a half headstand walking my feet up the wall to a right angle (as the picture shows).
We spent a lot of time concentrating on finding the length in the spine and working on keeping the elbow creases open. I find that if I imagine I have an egg in each elbow crease and I am trying not to crack them it helps to open the elbow creases and support the neck properly with the forearms.
This position is a lot more difficult for me so I am going to continue working on holding this position for a greater increasing time to build up strength and alignment. It is also nice to lift one leg straight up to increase the length in the spine, eventually I will lift both legs straight up but for now it's back to basics to build the strength to practice Sirsasana safely!