Clavicle X-ray is performed in a horizontal position (lying) or vertical (standing) - in frontal and lateral projections; an axial view of the clavicle may be required.
The technique for carrying out this diagnostic procedure includes correct placement (position) of the patient, positioning of the cassette and centering of the X-ray tube, which should ensure that an adequate image is obtained. 
Frontal image in a direct posterior projection requires laying the patient on his back (straight arms are parallel to the body); pictures in frontal projection are taken either in a horizontal position (the patient lies on his stomach) or standing (from the back).
The image in the axial projection (lying on the back with a contralateral rotation of the head) allows you to determine where the bone fragments were displaced during the fracture of the clavicle.
What can be seen on an X-ray of the clavicle?
An X-ray of a healthy clavicle / X-ray of a clavicle normally gives a clear (light) image of the contour of the bone body, its ends - the sternum and shoulder, joints (acromioclavicular and sternoclavicular), as well as the humeral process of the scapula. 
All structures are anatomically correct, there are no darkening. 
X-ray signs of a clavicle fracture include the presence of a darkening zone on the contour of the bone body in the form of a crack of various widths and configurations (indicating a violation of the integrity of the clavicle) and a lower displacement of its distal part. Often, clavicle fractures are displaced by a combination of the weight of the upper limb pulling the distal fragment downward and the sternocleidomastoid muscle pulling the medial fragment upward. But in a proximal fracture, good ligament support prevents displacement. 
Dislocation of the clavicle on X-ray is determined by the position of the lower edge of the clavicle: when the sternoclavicular joint is dislocated, the image shows the displacement of the sternal end of the clavicle upward. And with dislocation of the acromioclavicular joint, the lower contour of the clavicle and the lower contour of the humeral process of the scapula are at the same level.