Hi everyone! I have a 4 tiered cake that the customer wants 3 tiers to be styrofoam and have sheet cake servings. My question is Can i put fondant on the styrofoam ahead of time(a week) without it drying out? I also heard that fondant on styrofoam ends up looking dry. is this true? if so, then what can I use to make it look shiny(not too shiny)

Thanks!