I like to take a list of what I would like to buy like notions, sewing machine accessories, new products that I have read about etc., but I also add in on my list what I can buy it for on-line or at LQS so I know if it's a good deal or not.
Dressing in layers so you can take a light jacket off (or leave in bus/car) etc is also good. Don't count on being able to return to a previous booth to buy something unless it is not overly popular. I went last year, and my friend decided later on that she wanted a particular line of fat quarters we had seen in several places on Thursday, but by Saturday, no one had any left!
ENJOY, I am envious, no quilt trip for me this year.