While civilians typically aren't boosting themselves up to be arrogant, obnoxious or to brag, it can seem that way to someone from a background that frowns on self-marketing.
Whether you're exiting the military and looking for a first job, looking for a better job or looking to keep your job, LinkedIn is a powerful positioning tool to help others learn more about you and what you offer.
To grow in your career, you need to show what you can offer in the future: This requires a clear value proposition, visibility, a network of contacts and focus on a career direction.