Coral is a color that reminds us of the sea. a coral dress must be appropriate for a beach wedding.so something sunny and shiny should be used to decorate the dress. When choosing the nail polish, you can go with a natural color with shimmer. That is always the best way to go when your are wearing colors like that.it will highlight your fingers and toes under the sunshine. You COULD also use pink but I’m afraid it would throw off your outfit. And if you did a coral polish you would be driving yourself nuts trying to find the shade that matches perfectly. So something natural would be most fit.I would recommend something sparkling. As the coral is a dark color which is dark red., so you should use some light shinning colored polish to brighten up the dress. I think gold or silver is an proper option. These two colors are glossy and will make your whole appearance charming and sunny.