AI have to cover a 10" x 4" hexagon cake with black fondant (the worst!!) Any advice. Any time I've covered with black, it's disastrous. Thinking about panels, but never did that before. Please help. Working with FondX Elite black. Thanks!!

I've never done that. but buying black fondant was a good place to start. Trying to make it is always a disaster for me! Good luck

Three thoughts.  1.) knead in extra powdered sugar to make it sturdier 2. Or knead in some CMC, Tylose powder to make it stiffer and 3.) roll it out on a mat that's been covered in Crisco.  This eliminates the need for steaming the fondant afterwards to get rid of extra powdered sugar.  I buy black and red and purple too (Duff's), then use it as is or add it to my own MMF to help boost the color.