Depending on your climate, taking a hot shower outside is pretty much the best thing ever. It's also super easy to set up for yourself.
how to make a hot water outdoor shower
Basically, you want to order a propane instant hot water heater (preferably with an included shower hose/head and gas hose), get an exchangeable 20 lb propane tank (available at most gas stations), and hook these up to a source of water through an on/off valve (for turning your shower on and off). The heater is pressure-activated, meaning that it will instantly start sucking gas, ignite, and begin heating water when the water begins flowing in. You can adjust flow and temperature with the knobs on the front of the unit, and adjust the spray settings on the shower head. For runoff water, you can either choose a place with a drain, a spot in the garden that needs/can handle a decent amount of water, or set up a water catchment system that enables you to recycle your gray water and use for your plants, etc. Here's how to set up the mechanical parts:
A) propane instant water heater - $95
B) 20 lb exchangeable propane tank - ~$60/ $20 per refill after that (each refill should last a few months with daily use)
C) Gas feeder hose (included with water heater)
D) yellow gas tape for sealing gas connection with heater - $4.25
E) teflon tape (included with water heater) - $4.48
G) garden hose-to-1/2" connector - $10.38
H) garden hose on/off valve - $14.95
I) garden hose - $19.99
J) garden hose splitter (included with garden hose on/off valve)
K) 2x D batteries ~ $2
total cost: $214.61
Connect your bits, following the diagram above, and remember to wrap teflon tape around the male (exposed) threads (give it maybe 2-5 wraps per joint), and where the gas meets the water heater, use yellow gas tape in a similar fashion. Hang the heater unit on a screw head (screw in a sturdy screw onto the mounting surface, leaving a centimeter of screw exposed), and position the propane tank below this, with the tank's valve set to 'open'. When all is set up, close your garden hose on/off valve (H), open the feeding side of your hose splitter (J), and close the other side of the splitter, and turn on your spigot. If you've properly connected everything, there shouldn't be any leaks anywhere, despite the water being 'live' inside of your feeder hose and connections. If no leaks are present, just leave your spigot on, and control the on/off to your shower from the on/off valve (H) right below your heater. Make sure your batteries are inside of your heater, switch the unit ON, and try testing the heater. Water flow should ignite the heater, and after 5 seconds or so, your water should be hot. Adjust the gas and water flow valves to get a temperature you like, and you're done! I leave the aesthetics up to you, but keep in mind that if your water is not going into a drain, you might want to consider only using biodegradable soap so that you do not damage your plants or soil.