I'm starting a Job on saturday of replacing a shower and the ceramic tile. I Know I have to gut the the area where the shower is and also the tile, After i get the Liner out and the tile down I start fresh. Which part do i start first? The guy had asked 12X12 tile on the walls, do I put up drywall or plywood to put those type of tiles on? Or Do i replace the shower liner first and then put up the walls then the tile?