Your headline is the first line anyone reads after your name, and it shows up everywhere: search results, connection requests, comments, and every message you send. The default is just your current job title and employer, which wastes 220 characters that could be doing real work for you.
A strong headline does three things at once:
Says what you do
Clearly, and not as a vague label like "professional" or "expert".Signals the value you create
Who you help or what you produce for them, not just a title.Uses searchable keywords
The words people in your field actually type into the search box.
It is a positioning statement, not a job title, and it is worth treating that way.