Would turqouise and coral colour blocking look good?

Deep coral is gorgeous. I think you should definitely go with turquoise colours on your nails. And for your shoes do not match your dress. Don't make it too stark, like don't do black, maybe nude or another nice colour. If the focus is your dress then don't make anything very obvious. I've also read somewhere that you shouldn't match your eyes with your dress, so go for something that pops for your eyes :) So yeah, turquoise colour on your nails would be fine. Absolutely gorgeous. Have fun!