I'd at least go Friday and Saturday. Thursday evening you get the JJP Fireside chat and later me. Not a lot on Sunday unless you are in the tournament.
Read the schedule. Make plans on what you'd like. And be happy if you do half of them.
Assert yourself. You get out of Expo what you put into it.
I'd bring a light coat. You can check many weather websites in advance to help you like : https://www.wunderground.com/forecast/us/il/chicago/60290
Try and find LTG and get mugged.
LTG : )