Side Angle Pose

Utthita Parsvakonasana / Extended Lateral Angle Pose
Utthita means extended, Parsvo means side, kona means angle 

Start in Tadasana/mountain pose. Inhale and and spread the legs by having your right foot at 90 degree angle and your left foot at 45. The distance between your feet are 4 to 4 and a half apart (it also depends on your height). Exhale and raise the arms to the side and keep them in one line. Palms facing down and engage your arms.
Bend your right knee and try to keep your right femur or thigh bone parallel to the floor then bring your attention to your left leg, keep it straight and engaged by activating your quadriceps and TFL. Keep your right toes lifted to activate the arch of the foot.
Bring your right hand to the outside of your right leg, you can keep your palm or fingertips on the mat or on a block (whatever height works for you). Press the outer knee (right knee) to your arm to engage your gluteus and TFL. Stretch your left arm out and over your ear & keep it straight and engaged. Also bring your attention to the back body including your spine. Lengthen the spine and feel the skin on your back getting stretched and your side body is getting lengthened. 
Make sure you are breathing while you are paying attention to the anatomical details of the pose. 

Overall this pose stretches the entire side of the body because your arm is extended above the ear and the outer edge of the food is anchored with a straight and engaged leg. The chest, hips and the legs should be in one line.