Outdoor showers are a somewhat common option in nomadic living vehicles, because an in-vehicle shower takes up so much valuable living space. Moving it outdoors can be a big space saver, but it only is useful during warm weather and in places where it's acceptable to take a shower outdoors. Usually, these showers are used while wearing a bathing suit, but some nomads hang shower curtains around their outdoor shower area, or set up a pop-up shower tent.
Some nomads don't have a dedicated outdoor shower, but use a sprayer or detachable faucet from their sink and pull it outside of the vehicle to use as a shower.
Camping showers or solar showers can be used away from the vehicle. A vinyl bag is filled with hot water and then hung from a tree branch or other high point. See also portable showers.
If you will shower next to your vehicle with a hose and showerhead attached to the side or rear of your vehicle, you may be able to attach a tarp or shower curtain between your the upper corners of your open doors so that you can have some privacy while you shower. If that doesn't work with your vehicle, try wearing an opaque rain poncho which allows you to be fully covered while still being completely naked while cleaning yourself; you can insert your showerhead into the neckline or bottom of your poncho as needed. A portable pop-up camp shower tent may work well also.
