Avoid hyper-extending the neck as this can effect positioning
Centre in midline over C3-4
Collimate to ensure entire cervical spine is included
Ensure L/R marker in primary beam.
What to look for
All vertebrae clearly seen, and no rotation - spinous processes should be equal in size
Gentle extension of the neck can help with getting the spine straight, but if over extended can cause the base of the skull to superimpose over the C1 and C2 vertebrae, and lift them from the cassette.