I’ve already written about the basic alignment or body position in extended side angle pose or utthita parsvaokonasana or watch the video version.
But a small adjustment in the position of your feet and ultimately your hips can make a big difference on whether you feel the stretch and whether it has a negative impact on your lower back, pelvis and sacrum.
This brief video explains how to position your hips and feet to keep your pelvis and lower back happy and safe in extended side angle pose.
To get an idea of why the position of your feet and hips matter, check out the photos at the bottom of this article from Yoga Anatomy. While a different pose, the image of how the spine moves relative to your hips is important to understand.
The feet and hip alignment is similar to triangle pose.