This is part two of my job fair post dealing with what to do after you get home. At most job fairs, thousands of people are competing for far fewer jobs and you get a few seconds to make an impression. Fortunately, you can still make a dent after you've returned home just as long as you get a business card. For part one and tips on how to prepare in advance of a job fair check out this link.
Send a Thank You
Be sure you get a business card from the booths you visit at a job fair and try to get something memorable out of the conversation that will help you spark the person's memory later. When you return home send a thank you note to the contact info on the card. You should use whatever you discussed as a way to personalize it and possibly help them remember you.
Keep in Touch
Hopefully, when you send that thank you, you will get a response. Use this as an opportunity to establish a rapport and build some sort of relationship with this person. Follow the company and discuss what you read with your new contact or ask them for advice or info about their field. Most importantly, be human and be considerate, don't just send a new and impersonal message hoping to get a response or you probably won't.