Career Fairs are held all over the country for various populations of employers or graduate/professional schools and candidates. They are usually held in a single large space with each employer or graduate/professional school at a single table decked out with exhibit materials. Career Development hosts a Philadelphia Not for Profit Career Fair each year in February and is a member of a consortium which hosts Not for Profit Career Fairs in Boston in the spring.
Try to obtain a list of the organizations attending the fair and do a little research on them to determine which organizations are of greatest interest to you in advance.
In advance or first thing upon your arrival, find out where the organizations you are most interested in are located in the room. As soon as you enter the fair, scope out the lines for the organizations of greatest interest to help you to determine how best to use your time while at the fair. It helps to have prioritized your interests in advance.
Get there early so you can make the most of the time you will have available. You can spend a lot of time waiting in line to talk to a popular organization.
Dress professionally. You will be making a first (and lasting) impression.
Make sure you have plenty of copies of your resume to give to the organizations you speak with.
Meet each person with a confident hand shake.
Ask each person you speak with for a business card. Make notes on the back of the cards to help you to develop customized follow up / thank you letters/emails.
Have follow up / thank you letters/ emails out by the end of the next day.