People tend to tighten and raise their shoulders when they are nervous and this causes a couple of problems. It makes your shoulder appear narrower than they really are, your neck seems shorter, and worse, it creates a feeling and look of tenseness.
To be able to do this pose, you have to concentrate on relaxing your shoulders - let them fall naturally.
Hunching your shoulders makes your neck appear shorter (left)
Relaxing your shoulders instantly makes you look more natural and less tense (right)
More tips to come. Taken from one of my favorite blogs bridaltwist