I usually elevate the front to let water bead out the rear. I follow the same washing procedures I do on the outside of a truck depending on how dirty the bed is, etc. From there depending on the bed (rhino liner, plastic bed liner), I work accordingly. To be honest, it has probably been ten years since I have seen a truck without some sort of bed liner. Plastic liners I usually wash and dry and do not provide any sort of shine unless asked by the owner to do so.