This space right beneath your profile photo on your LinkedIn profile is where you can insert a little narrative about yourself and speak directly to potential clients. Here, you can help people understand the industry, business, products, talent, or other aspect that you're pitching.
Don't lie, or try to be someone you're not, but do take the opportunity to show like-mindedness by using industry-specific keywords. How can you identify these keywords? By seeking out and reading how respected professionals in the industry describe themselves. Pick up on common phrases and industry- or strengths-related keywords and integrate them into your profile.