Inhale - Come forward to a low cobra. Try not to press into your hands as you come into the back bend.
If you did chaturanga dandasana in the previous step:
Inhale - Roll over your toes (if possible) to come into an upward facing dog. Bend your elbows out to the sides at first in order to get your shoulders down away from your ears. Then straighten your arms. Make sure your legs are straight and the knees are lifted off the floor.