Your first plan probably should be to find the information page for the particular show you want to enter. Membership is required for some show entries. Specific types of quilts are required for others. Others require that submissions be "juried" first...which means passing an entry inspection for deisgn/size/quality/etc. by sending a photo to the show committee for their acceptance. And these always have certain restrictions and rules for this juried submission.
On the internet, search for "quilt shows" or "national quilt shows" to find some near you. They usually have a page that tells you this sort of information.
Then you can study the American Quilt Society web site, The National Quilt Association, and other large quilting organizations for their suggestions for award winning quilts. Are you a local quilt guild member? Maybe their library has books on the subject. Or google "how to make award winning quilts".
Good luck with your submission!
Jan in VA
Jan in VA