I wanted to surprise my boyfriend by redoing our bathroom while he was away..I took down the wallpaper (using a steamer), but I'm not sure what to do next. It looks like there are a few rips in the "cardboard looking stuff", am I supposed to plaster over that and sand it down smooth, or do I just get primer paint and cover the whole wall? Ultimately I am going to paint the wall (not put up more wallpaper).