Best of luck at I-CON 32, one good thing to know is to always smile, even if someone says no or insults your book. Image and presentation is a big deal and as long as you look friendly people usually won’t have a hard time listening to a sell.
I’ve never been to a con as a vendor (YET) but we do have a few authors here who have - @Rick Heinz , @Jamison Stone ... I’m sure there are others. Hopefully they will pop in and give some advice. :D Good luck!
"After a surveillance culture has taken control over the galaxy, it’s up to an eclectic group of misfits from disparate corners of the cosmos to rediscover the forbidden concepts of life, love and liberty."