If you notice one shoulder is lower than the other, then often times your neck is shifted to that side. This applies the same to the hips. If your pelvis or low back shifts to the left, then the left hip will drop.
If you see that your chin is more to one side or you can see one ear more than the other then your neck may be rotated slightly.
If one ear is lower than the other or you can’t imagine a straight line across connecting through both eyes or ears you may have a slight head tilt.
All of these observations make you aware that there are most likely those same shifts inside you of your cervical spine.
Another thing to look for is forward neck posture. This is when the head juts forward compared to the shoulder. In severe cases you will notice this when looking in the mirror; simply turn a bit to try to see yourself from the side. If you have any of the above postural misalignments especially forward head posture, I would start using a neck pillow at night, and do specific neck exercises to correct your posture.
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