If you put some effort into your profile, it can be a useful tool. You will have to apply to jobs for the quickest result; it doesn't replace doing that. If there is a place you'd like to work, you can search the company on LinkedIn, see what type of experience they have and connect with them.
It's smart to think about this now. I wish I had started my LinkedIn profile before I was in college because I met so many interesting professionals who could have helped me after I graduated.