Drawing around a bum

I want to record actual shapes of people, so i tried using myself. The drawing on the left; i drew around myself with my back to the wall (where the paper was taped), this gave me good waist definition, but did not replicate the view of a bum as the shape of the front of your pelvis is different to the back. So, the image on the right, i stood with my front facing the wall and drew around myself again. This one worked really well as it showed the more smoother out shaped that you get from the rear.

This will come in useful when recreating the shapes in my practice, it will also be a great way to collect some primary research.

Drawing around a bum