We shower quite often when camping. Unless it is cold outside, we use the outside shower faucet ala natural when boondocking or with our pop-up tent:
http://www.evergreen-outdoors.net/outba ... _privy.htm
There are also a lot of showers which can be rented by the minute. For example, in the east side of the Sierras, there are a number listed on:
We still occasionally use our porta shower....it is very nice to be able to have a full shower when there is no other option.
The bottom of the vinyl walls snap into the "bottom pan" but the walls don't connect to the "canvas" walls of the SMB...there are instead connectors which screw into the penthouse ceiling to hold up the top of the shower walls. The shower walls have the companion part with a slot for these fittings...hard to describe but it is very easy to put the shower up. The shower has a zipper....open the zipper, strip and step in, zip up the shower, and enjoy a shower. We find that we can both take a "Navy" shower and not overflow the tub. We also have a portable wood shower deck from Camping World to stand on in the shower and that keeps our feet out of the water:
http://www.campingworld.com/shopping/it ... deck/24478
(This shower deck is also nice when using rental showers.)
Emptying the shower box when you are finished was once a problem. Some campgrounds won't let you dump gray water out on the ground which means that the waste water has to go into the sink/grey water tank. Even if you can dump the water, it is not that simple to carry the full tub out to dump it and not accidentally spill it. I solved that problem with a small 120v waterfall pump. When you are all done, I plug in the pump and pump the waste water into the sink. The water which can't be picked up can be easily mopped up with a towel. The pump is stored in the shower box itself.
The walls of the shower need to be dried off when you are done. If it is sunny outside, we just open the shower up and lay it on the picnic table. Otherwise, we dry it with a towel the best we can and completely dry it when we get home.