These are informal "can I take you out to coffee?" talks with people in your industry to see what they are working on, what is happening with them, what is going on in the industry. Every job I have ever gotten is through informal meetings with people I have met through my network (whether its the current newspaper, your friends, parents, relatives, or other).
At the end of every one I ask: "Is there anyone else you think I should talk to?" and "Do you currently have any opportunities at your company for me?". Rinse repeat.
I guarantee investing in 30 informational interviews will yield huge dividends vs. 30 career fairs, a personal pitch deck, starting a blog, dusting off your resume, or God Forbid: applying to jobs through Linkedin.