Having judged quilts at fairs my suggestion is to:
Read the rules carefully and enter accordingly
Also you might check the prizes given to decide the category you want to make a quilt and enter.
Try and find out who the judges are. Knitters may be judging the quilts.
Are you familiar with the specific fair. Is there a lot of good competition. What is the overall quality.
Why are you entering - for the prize, ribbon, to have your quilt critiqued etc. Some fairs are prestigious while others not.
Will your entry be displayed appropriately or are the uilts just hanging over a rope stretched between two poles.