I use pre-cut polystyrene cake boards/drum that I usually cover will tin foil, I would love to start covering them in fondant but I'm not sure how to do it. Do I need to cover it with foil or something else first before the fondant or can I glue the fondant directly onto the polystyrene - obviously telling people that it is not to be eaten.
Any help, much appreciated

I would cover it with saran wrap, then brush piping gel or corn syrup over it and place the fondant over it and smooth like normal.

Ah ok, thanks!