If you want to improve the appearance of your RV toilet and shower, then you could add a shower enclosure around the area. An enclosure will consist of a series of walls, plus a door which allows access to the RV toilet and shower area. An enclosure can easily be made using some hardwood boards.
Step 1 - Make the Enclosure
You will need to begin by making the top frame, and then install it into the RV toilet and shower space by nailing the posts to the side of the walls. You should then fit the bottom part of the frame in the same manner at the base of the shower space.
Step 2 - Build the Walls
You should then add the walls. This will involve cutting down some hardwood sheets until they fit the area that you have planned for the enclosure. Screw the wooden boards into the frame using some bolts. Tighten these to secure the frame. You should then add hinges for the door panel, and fix this to two horizontal posts at the front of the RV toilet and shower.