Commercial platforms like those made by Faller and others were way too expensive for my purse. I had the idea of using styrofoam. This stuff is available in various thicknesses from home depots and is not very expensive. Being an N-scaler, I use 10 mm (0.4") and cut them to fit the tracks. To glue them down, special styrofoam contact cement, white glue, or caulk may be used. To give the platform a proper look, I use thin cardboard in black (for a tar deck) or grey cardboard. and so I have a ready - to - detail platform within 10 minutes time.