Beginner: Needle is an exciting and beautiful pose for beginners. It is a challenging pose that strengthens your legs and elongates your spine. Focus on dropping the weight of the head down to counterbalance the lift of the leg. Use your hands for balance and make sure to keep your weight evenly distributed across your hands and all of your fingers. Remember: however high you lift your leg is fine.
Advanced: To deepen into needle pose, use the energy of the standing leg. Send energy down through that leg by pressing into the ground with the whole foot. Now pull power up through the arms and all the way up to the lifting toes. Keep the weight of the head dropping down and the lifting leg rising up.