What do I Use??????

I ripped all of my interior peices out of my car and i want to wrap everything in tweed. i took off the old vinyl on the doors and started sanding down all of the plastic parts. What grit of sand paper should i use to rough up the panels. i also heard that there is a HUGE difference in what kind of padding/matting/or backing that you use. What is the right type of glue to use so everything will stick together.