One of the biggest mistakes that people make with Linked In is just copying and pasting their resume. Recruiters and hiring managers want to see a narrative of your background. On a resume, you shouldn’t use personal pronouns. On LinkedIn, however, you can be more personal in your background. The background should give very high-level details about you. That way, if a potential employer reads nothing else, they get a good sense of what you have accomplished in your career.
Underneath each position that you held, give an overview of your accomplishments, key strengths and skills that employers would be interested in. Remember, statistically, 93%-94% of employers will research you online and LinkedIn is one of the top places that they will look. LinkedIn may be even more important than your resume in getting you that job. People often Google candidates to see what comes up. LinkedIn is almost always at the top of the search results.