One other trick for you...
You'll need polystyrene foam. The kind that will dissolve in gasoline. You shape it to your liking and put the glass and resin over it. Once you have the shape, you use gasoline to dissolve the foam out. You need to use the epoxy resin on this. The polyester stuff will dissolve the foam just like gasoline. Again... make a couple of small test piece before you go large to get the feel of it.
https://www.youtube.com/watch?v=FJYNmJOwPH0
https://www.bing.com/videos/search?q...7D&FORM=VRDGAR
also... Use gloves and at least a dust mask. fibers in your lungs is bad.