Setup and Key Actions
Set up the pose in ardha parsvottanasana (pyramid pose with a “flat back”—not folding forward) with your right foot forward. Press all of your fingertips into the floor or blocks. Lengthen your spine, and reach the crown of your head (not your chin) straight ahead. Draw the left side of your belly toward the right side of your belly, and lift your back inner thigh up. Move your front outer hip back. Bring your right hand to your sacrum and continue to lengthen. Place your left fingertips on the floor or a block outside your right shin, pressing forearm against shin, shin against forearm for bonus stability and core activation. Keep the length in your spine, and on an exhale, twist right, twisting primarily in your middle back. If your shoulders are totally stacked, you can stretch your top arm straight up, otherwise keep your right hand on your pelvis. Keep the back of your skull and the back of your tailbone aligned (so that your head isn’t dropping forward or back). Look straight ahead, or turn your head to look up if that's comfortable for your neck
Keep your left fingertips right where they were for ardha parsvottonasana, on the floor or on a block, instead of moving them outside your front shin as you move into revolved triangle.