Beginner: A fun posture for a beginner to attempt, do not get lost in trying to perfectly execute crane balance! There are many phases to learning the posture, have fun with it. Place your focus in the placement of the hands, make sure your hips are even, and extend your head out, not down, as you attempt the balance.
Advanced: To deepen in Crane, really contract the abdominals and place your legs as high up on the shoulders as possible. This will allow you to lift your body even higher. Are your feet energized? They should not hang, stagnant, but be active and ready for your descent back to a crouch. Push your middle finger solidly down to get a good strong lift through the arms.