Focus on the circle lock at all times. You do not have to tap in any particular location on the screen. Tap anywhere without blocking your view to stop the spinning circle. After you hit one lock, the circle will immediately reverse direction. The next lock can be very close or far away. You must be ready to tap quickly if the lock is close. Focus on the entire ring and not just the red bar. You may be able to notice the locks coming faster, and thus have more reaction time. Locks are never in the same location in a level. If you need to restart, you may get an easier placement pattern.