If you've never been to it, it can be a bit overwhelming. I would advise downloading and studying the overall map and the individual field maps to see how the rows and vender spacing are laid out and how everything goes together.
Hershey Field maps and other useful info:
http://hersheyaaca.org/fm_information.html
Lots of walking- easily three days worth if you take your time. Plenty of good ole junk food vendors to clog your arteries. Some times you can get in traffic jams waiting to get parked - especially if the parking fields are muddy from rain. You can buy vendors directory(recommended) at the various free entry points.
If your staying outside the Hershey area and driving in , it's best to use I-81 and get off at the SR 39 south (Hershey exit) - it's about 6 miles more or less to the Hershey Park / Giant Center complex where it's at. The US322/422 routes from Harrisburg can really get clogged with traffic in the morning so I would avoid them.
Wish I could go but my feet and legs can't handle it anymore
Hope this helps - Have an enjoyAble time
Jon in Ohio