Lie prone on the floor. Stretch your legs back, with the tops of your feet on the floor. Bend your elbows and spread your palms on the floor beside your waist so that your forearms are relatively perpendicular to the floor.
Inhale and press your inner hands firmly into the floor and slightly back, as if you were trying to push yourself forward along the floor. Then straighten your arms and simultaneously lift your torso up and your legs a few inches off the floor on an inhalation. Keep the thighs firm and slightly turned inward, the arms firm and turned out so the elbow creases face forward.
Press the tailbone toward the pubis and lift the pubis toward the navel. Narrow the hip points. Firm but don't harden the buttocks.
Firm the shoulder blades against the back and puff the side ribs forward. Lift through the top of the sternum but avoid pushing the front ribs forward, which only hardens the lower back. Look straight ahead or tip the head back slightly, but take care not to compress the back of the neck and harden the throat.
Urdhva Mukha Svanasana is one of the positions in the traditional Sun Salutation sequence. You can also practice this pose individually, holding it anywhere from 15 to 30 seconds, breathing easily. Release back to the floor or lift into Adho Mukha Svanasana with an exhalation.