From what I've read, if you *think* your curling/pulling with your elbows, you are. Practice from the hang position, dropping under the bar, and catching in the rack. From the floor, pull to a "high" hang position, right around your shoulders, don't use your arms, pull hard from the floor and shrug/extend your hips at the top let the momentum carry it upwards. If you are just learning, you should consider trying the full clean (with the squat) rather than the power clean.