Most small cove molding is the same height on either side, but it's better to double-check. Other than that, it's really that easy — just nail the trim ... wallpaper. Peel-and-stick faux ...

While there are various types of wainscoting, such as board and batten and picture frame molding ... that won't damage the wall, you can use this ReWallpaper Faux Beadboard Peel and Stick version.