Look on the entry form. Sometimes the entry materials will give you a good indication of the judging criteria. I found it helpful to show my quilts early on because the feedback, both from judges, and casual viewers, really helped me. Quilt police may pose as judges, so be forewarned.
I am not a great technical sewer - anything I make will have sewing errors, but I create my own designs and most have an artistic likability. If I was judged solely on execution, I'd be disappointed.